[{"oa_version":"Published Version","title":"Magnetic activity evolution of solar-like stars. I. Sph–age relation derived from Kepler observations","day":"01","author":[{"first_name":"Savita","last_name":"Mathur","full_name":"Mathur, Savita"},{"first_name":"Zachary R.","full_name":"Claytor, Zachary R.","last_name":"Claytor"},{"full_name":"Santos, Ângela R. G.","last_name":"Santos","first_name":"Ângela R. G."},{"first_name":"Rafael A.","last_name":"García","full_name":"García, Rafael A."},{"full_name":"Amard, Louis","last_name":"Amard","first_name":"Louis"},{"first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000","last_name":"Bugnet","full_name":"Bugnet, Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501"},{"last_name":"Corsaro","full_name":"Corsaro, Enrico","first_name":"Enrico"},{"first_name":"Alfio","full_name":"Bonanno, Alfio","last_name":"Bonanno"},{"first_name":"Sylvain N.","full_name":"Breton, Sylvain N.","last_name":"Breton"},{"first_name":"Diego","last_name":"Godoy-Rivera","full_name":"Godoy-Rivera, Diego"},{"first_name":"Marc H.","last_name":"Pinsonneault","full_name":"Pinsonneault, Marc H."},{"last_name":"van Saders","full_name":"van Saders, Jennifer","first_name":"Jennifer"}],"date_created":"2023-08-01T14:19:16Z","article_type":"original","volume":952,"tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png","short":"CC BY (4.0)"},"abstract":[{"lang":"eng","text":"The ages of solar-like stars have been at the center of many studies such as exoplanet characterization or Galactic-archeology. While ages are usually computed from stellar evolution models, relations linking ages to other stellar properties, such as rotation and magnetic activity, have been investigated. With the large catalog of 55,232 rotation periods, Prot, and photometric magnetic activity index, Sph from Kepler data, we have the opportunity to look for such magneto-gyro-chronology relations. Stellar ages are obtained with two stellar evolution codes that include treatment of angular momentum evolution, hence using Prot as input in addition to classical atmospheric parameters. We explore two different ways of predicting stellar ages on three subsamples with spectroscopic observations: solar analogs, late-F and G dwarfs, and K dwarfs. We first perform a Bayesian analysis to derive relations between Sph and ages between 1 and 5 Gyr, and other stellar properties. For late-F and G dwarfs, and K dwarfs, the multivariate regression favors the model with Prot and Sph with median differences of 0.1% and 0.2%, respectively. We also apply Machine Learning techniques with a Random Forest algorithm to predict ages up to 14 Gyr with the same set of input parameters. For late-F, G and K dwarfs together, predicted ages are on average within 5.3% of the model ages and improve to 3.1% when including Prot. These are very promising results for a quick age estimation for solar-like stars with photometric observations, especially with current and future space missions."}],"intvolume":"       952","has_accepted_license":"1","file_date_updated":"2023-08-02T07:42:26Z","publication_status":"published","publication_identifier":{"issn":["0004-637X"],"eissn":["1538-4357"]},"month":"08","file":[{"file_id":"13448","creator":"dernst","date_updated":"2023-08-02T07:42:26Z","file_size":4192386,"date_created":"2023-08-02T07:42:26Z","checksum":"f12452834d7ed6748dbf5ace18af4723","relation":"main_file","content_type":"application/pdf","access_level":"open_access","file_name":"2023_AstrophysicalJour_Mathur.pdf","success":1}],"article_number":"131","department":[{"_id":"LiBu"}],"language":[{"iso":"eng"}],"oa":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","citation":{"chicago":"Mathur, Savita, Zachary R. Claytor, Ângela R. G. Santos, Rafael A. García, Louis Amard, Lisa Annabelle Bugnet, Enrico Corsaro, et al. “Magnetic Activity Evolution of Solar-like Stars. I. Sph–Age Relation Derived from Kepler Observations.” <i>The Astrophysical Journal</i>. American Astronomical Society, 2023. <a href=\"https://doi.org/10.3847/1538-4357/acd118\">https://doi.org/10.3847/1538-4357/acd118</a>.","ista":"Mathur S, Claytor ZR, Santos ÂRG, García RA, Amard L, Bugnet LA, Corsaro E, Bonanno A, Breton SN, Godoy-Rivera D, Pinsonneault MH, van Saders J. 2023. Magnetic activity evolution of solar-like stars. I. Sph–age relation derived from Kepler observations. The Astrophysical Journal. 952(2), 131.","apa":"Mathur, S., Claytor, Z. R., Santos, Â. R. G., García, R. A., Amard, L., Bugnet, L. A., … van Saders, J. (2023). Magnetic activity evolution of solar-like stars. I. Sph–age relation derived from Kepler observations. <i>The Astrophysical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-4357/acd118\">https://doi.org/10.3847/1538-4357/acd118</a>","mla":"Mathur, Savita, et al. “Magnetic Activity Evolution of Solar-like Stars. I. Sph–Age Relation Derived from Kepler Observations.” <i>The Astrophysical Journal</i>, vol. 952, no. 2, 131, American Astronomical Society, 2023, doi:<a href=\"https://doi.org/10.3847/1538-4357/acd118\">10.3847/1538-4357/acd118</a>.","ama":"Mathur S, Claytor ZR, Santos ÂRG, et al. Magnetic activity evolution of solar-like stars. I. Sph–age relation derived from Kepler observations. <i>The Astrophysical Journal</i>. 2023;952(2). doi:<a href=\"https://doi.org/10.3847/1538-4357/acd118\">10.3847/1538-4357/acd118</a>","ieee":"S. Mathur <i>et al.</i>, “Magnetic activity evolution of solar-like stars. I. Sph–age relation derived from Kepler observations,” <i>The Astrophysical Journal</i>, vol. 952, no. 2. American Astronomical Society, 2023.","short":"S. Mathur, Z.R. Claytor, Â.R.G. Santos, R.A. García, L. Amard, L.A. Bugnet, E. Corsaro, A. Bonanno, S.N. Breton, D. Godoy-Rivera, M.H. Pinsonneault, J. van Saders, The Astrophysical Journal 952 (2023)."},"issue":"2","publisher":"American Astronomical Society","article_processing_charge":"Yes","doi":"10.3847/1538-4357/acd118","type":"journal_article","_id":"13443","date_updated":"2023-12-13T12:00:15Z","ddc":["520"],"quality_controlled":"1","external_id":{"isi":["001034185700001"]},"isi":1,"year":"2023","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"status":"public","publication":"The Astrophysical Journal","date_published":"2023-08-01T00:00:00Z","acknowledgement":"This paper includes data collected by the Kepler mission and obtained from the MAST data archive at the Space Telescope Science Institute (STScI). Funding for the Kepler mission is provided by the NASA Science Mission Directorate. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5–26555. We acknowledge that this research was supported in part by the National Science Foundation under grant No. NSF PHY-1748958. S.M. acknowledges support from the Spanish Ministry of Science and Innovation (MICINN) with the Ramón y Cajal fellowship No. RYC-2015-17697, the grant No. PID2019-107061GB-C66, and through AEI under the Severo Ochoa Centres of Excellence Programme 2020–2023 (CEX2019-000920-S). S.M. and D.G.R. acknowledge support from the Spanish Ministry of Science and Innovation (MICINN) with the grant No. PID2019-107187GB-I00. Z.R.C. acknowledges support from National Aeronautics and Space Administration via the TESS Guest Investigator Program (grant No. 80NSSC18K18584). The work presented here was partially supported by the NASA grant NNX17AF27G. A.R.G.S. acknowledges the support by FCT through national funds and by FEDER through COMPETE2020 by the following grants: UIDB/04434/2020 and UIDP/04434/2020. A.R.G.S. is supported by FCT through the work contract No. 2020.02480.CEECIND/CP1631/CT0001. R.A.G., L.A., and S.N.B. acknowledge the support from PLATO and GOLF CNES grants. S.N.B. acknowledges support from PLATO ASI-INAF agreement No. 2015-019-R.1-2018."},{"title":"Asteroseismology with the Roman galactic bulge time-domain survey","oa_version":"Preprint","author":[{"first_name":"Daniel","full_name":"Huber, Daniel","last_name":"Huber"},{"first_name":"Marc","full_name":"Pinsonneault, Marc","last_name":"Pinsonneault"},{"last_name":"Beck","full_name":"Beck, Paul","first_name":"Paul"},{"full_name":"Bedding, Timothy R.","last_name":"Bedding","first_name":"Timothy R."},{"full_name":"Joss Bland-Hawthorn, Joss Bland-Hawthorn","last_name":"Joss Bland-Hawthorn","first_name":"Joss Bland-Hawthorn"},{"first_name":"Sylvain N.","last_name":"Breton","full_name":"Breton, Sylvain N."},{"last_name":"Bugnet","full_name":"Bugnet, Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501","first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000"},{"full_name":"Chaplin, William J.","last_name":"Chaplin","first_name":"William J."},{"first_name":"Rafael A.","last_name":"Garcia","full_name":"Garcia, Rafael A."},{"first_name":"Samuel K.","last_name":"Grunblatt","full_name":"Grunblatt, Samuel K."},{"last_name":"Guzik","full_name":"Guzik, Joyce A.","first_name":"Joyce A."},{"first_name":"Saskia","full_name":"Hekker, Saskia","last_name":"Hekker"},{"full_name":"Kawaler, Steven D.","last_name":"Kawaler","first_name":"Steven D."},{"first_name":"Stephane","full_name":"Mathis, Stephane","last_name":"Mathis"},{"full_name":"Mathur, Savita","last_name":"Mathur","first_name":"Savita"},{"first_name":"Travis","full_name":"Metcalfe, Travis","last_name":"Metcalfe"},{"last_name":"Mosser","full_name":"Mosser, Benoit","first_name":"Benoit"},{"full_name":"Ness, Melissa K.","last_name":"Ness","first_name":"Melissa K."},{"first_name":"Anthony L.","full_name":"Piro, Anthony L.","last_name":"Piro"},{"last_name":"Serenelli","full_name":"Serenelli, Aldo","first_name":"Aldo"},{"last_name":"Sharma","full_name":"Sharma, Sanjib","first_name":"Sanjib"},{"first_name":"David R.","full_name":"Soderblom, David R.","last_name":"Soderblom"},{"full_name":"Stassun, Keivan G.","last_name":"Stassun","first_name":"Keivan G."},{"last_name":"Stello","full_name":"Stello, Dennis","first_name":"Dennis"},{"first_name":"Jamie","last_name":"Tayar","full_name":"Tayar, Jamie"},{"full_name":"Belle, Gerard T. van","last_name":"Belle","first_name":"Gerard T. van"},{"last_name":"Zinn","full_name":"Zinn, Joel C.","first_name":"Joel C."}],"doi":"10.48550/arXiv.2307.03237","article_processing_charge":"No","day":"06","type":"preprint","date_created":"2023-08-02T07:30:43Z","date_updated":"2023-08-02T07:36:00Z","_id":"13447","abstract":[{"lang":"eng","text":"Asteroseismology has transformed stellar astrophysics. Red giant asteroseismology is a prime example, with oscillation periods and amplitudes that are readily detectable with time-domain space-based telescopes. These oscillations can be used to infer masses, ages and radii for large numbers of stars, providing unique constraints on stellar populations in our galaxy. The cadence, duration, and spatial resolution of the Roman galactic bulge time-domain survey (GBTDS) are well-suited for asteroseismology and will probe an important population not studied by prior missions. We identify photometric precision as a key requirement for realizing the potential of asteroseismology with Roman. A precision of 1 mmag per 15-min cadence or better for saturated stars will enable detections of the populous red clump star population in the Galactic bulge. If the survey efficiency is better than expected, we argue for repeat observations of the same fields to improve photometric precision, or covering additional fields to expand the stellar population reach if the photometric precision for saturated stars is better than 1 mmag. Asteroseismology is relatively insensitive to the timing of the observations during the mission, and the prime red clump targets can be observed in a single 70 day campaign in any given field. Complementary stellar characterization, particularly astrometry tied to the Gaia system, will also dramatically expand the diagnostic power of asteroseismology. We also highlight synergies to Roman GBTDS exoplanet science using transits and microlensing."}],"publication_status":"submitted","main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2307.03237","open_access":"1"}],"external_id":{"arxiv":["2307.03237"]},"month":"07","arxiv":1,"year":"2023","article_number":"2307.03237","department":[{"_id":"LiBu"}],"publication":"arXiv","language":[{"iso":"eng"}],"status":"public","oa":1,"date_published":"2023-07-06T00:00:00Z","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","citation":{"ama":"Huber D, Pinsonneault M, Beck P, et al. Asteroseismology with the Roman galactic bulge time-domain survey. <i>arXiv</i>. doi:<a href=\"https://doi.org/10.48550/arXiv.2307.03237\">10.48550/arXiv.2307.03237</a>","ieee":"D. Huber <i>et al.</i>, “Asteroseismology with the Roman galactic bulge time-domain survey,” <i>arXiv</i>. .","short":"D. Huber, M. Pinsonneault, P. Beck, T.R. Bedding, J.B.-H. Joss Bland-Hawthorn, S.N. Breton, L.A. Bugnet, W.J. Chaplin, R.A. Garcia, S.K. Grunblatt, J.A. Guzik, S. Hekker, S.D. Kawaler, S. Mathis, S. Mathur, T. Metcalfe, B. Mosser, M.K. Ness, A.L. Piro, A. Serenelli, S. Sharma, D.R. Soderblom, K.G. Stassun, D. Stello, J. Tayar, G.T. van Belle, J.C. Zinn, ArXiv (n.d.).","ista":"Huber D, Pinsonneault M, Beck P, Bedding TR, Joss Bland-Hawthorn JB-H, Breton SN, Bugnet LA, Chaplin WJ, Garcia RA, Grunblatt SK, Guzik JA, Hekker S, Kawaler SD, Mathis S, Mathur S, Metcalfe T, Mosser B, Ness MK, Piro AL, Serenelli A, Sharma S, Soderblom DR, Stassun KG, Stello D, Tayar J, Belle GT van, Zinn JC. Asteroseismology with the Roman galactic bulge time-domain survey. arXiv, 2307.03237.","chicago":"Huber, Daniel, Marc Pinsonneault, Paul Beck, Timothy R. Bedding, Joss Bland-Hawthorn Joss Bland-Hawthorn, Sylvain N. Breton, Lisa Annabelle Bugnet, et al. “Asteroseismology with the Roman Galactic Bulge Time-Domain Survey.” <i>ArXiv</i>, n.d. <a href=\"https://doi.org/10.48550/arXiv.2307.03237\">https://doi.org/10.48550/arXiv.2307.03237</a>.","apa":"Huber, D., Pinsonneault, M., Beck, P., Bedding, T. R., Joss Bland-Hawthorn, J. B.-H., Breton, S. N., … Zinn, J. C. (n.d.). Asteroseismology with the Roman galactic bulge time-domain survey. <i>arXiv</i>. <a href=\"https://doi.org/10.48550/arXiv.2307.03237\">https://doi.org/10.48550/arXiv.2307.03237</a>","mla":"Huber, Daniel, et al. “Asteroseismology with the Roman Galactic Bulge Time-Domain Survey.” <i>ArXiv</i>, 2307.03237, doi:<a href=\"https://doi.org/10.48550/arXiv.2307.03237\">10.48550/arXiv.2307.03237</a>."}},{"article_type":"letter_note","date_created":"2023-09-03T22:01:15Z","volume":676,"oa_version":"Published Version","title":"Asymmetries of frequency splittings of dipolar mixed modes: A window on the topology of deep magnetic fields","author":[{"first_name":"S.","full_name":"Mathis, S.","last_name":"Mathis"},{"first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000","last_name":"Bugnet","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle"}],"scopus_import":"1","day":"01","publication_identifier":{"issn":["0004-6361"],"eissn":["1432-0746"]},"publication_status":"published","file_date_updated":"2023-09-06T07:13:19Z","intvolume":"       676","tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png","short":"CC BY (4.0)"},"abstract":[{"lang":"eng","text":"Context. Space asteroseismology is revolutionizing our knowledge of the internal structure and dynamics of stars. A breakthrough is ongoing with the recent discoveries of signatures of strong magnetic fields in the core of red giant stars. The key signature for such a detection is the asymmetry these fields induce in the frequency splittings of observed dipolar mixed gravito-acoustic modes.\r\nAims. We investigate the ability of the observed asymmetries of the frequency splittings of dipolar mixed modes to constrain the geometrical properties of deep magnetic fields.\r\nMethods. We used the powerful analytical Racah-Wigner algebra used in quantum mechanics to characterize the geometrical couplings of dipolar mixed oscillation modes with various realistically plausible topologies of fossil magnetic fields. We also computed the induced perturbation of their frequencies.\r\nResults. First, in the case of an oblique magnetic dipole, we provide the exact analytical expression of the asymmetry as a function of the angle between the rotation and magnetic axes. Its value provides a direct measure of this angle. Second, considering a combination of axisymmetric dipolar and quadrupolar fields, we show how the asymmetry is blind to the unraveling of the relative strength and sign of each component. Finally, in the case of a given multipole, we show that a negative asymmetry is a signature of non-axisymmetric topologies.\r\nConclusions. Asymmetries of dipolar mixed modes provide a key bit of information on the geometrical topology of deep fossil magnetic fields, but this is insufficient on its own. Asteroseismic constraints should therefore be combined with spectropolarimetric observations and numerical simulations, which aim to predict the more probable stable large-scale geometries."}],"has_accepted_license":"1","article_number":"L9","file":[{"file_id":"14271","creator":"dernst","date_updated":"2023-09-06T07:13:19Z","file_size":458120,"date_created":"2023-09-06T07:13:19Z","checksum":"7b30d26fb2b7bcb5b5be1414950615f9","relation":"main_file","access_level":"open_access","content_type":"application/pdf","success":1,"file_name":"2023_AstronomyAstrophysics_Mathis.pdf"}],"department":[{"_id":"LiBu"}],"arxiv":1,"month":"08","user_id":"c635000d-4b10-11ee-a964-aac5a93f6ac1","citation":{"ama":"Mathis S, Bugnet LA. Asymmetries of frequency splittings of dipolar mixed modes: A window on the topology of deep magnetic fields. <i>Astronomy and Astrophysics</i>. 2023;676. doi:<a href=\"https://doi.org/10.1051/0004-6361/202346832\">10.1051/0004-6361/202346832</a>","short":"S. Mathis, L.A. Bugnet, Astronomy and Astrophysics 676 (2023).","ieee":"S. Mathis and L. A. Bugnet, “Asymmetries of frequency splittings of dipolar mixed modes: A window on the topology of deep magnetic fields,” <i>Astronomy and Astrophysics</i>, vol. 676. EDP Sciences, 2023.","chicago":"Mathis, S., and Lisa Annabelle Bugnet. “Asymmetries of Frequency Splittings of Dipolar Mixed Modes: A Window on the Topology of Deep Magnetic Fields.” <i>Astronomy and Astrophysics</i>. EDP Sciences, 2023. <a href=\"https://doi.org/10.1051/0004-6361/202346832\">https://doi.org/10.1051/0004-6361/202346832</a>.","ista":"Mathis S, Bugnet LA. 2023. Asymmetries of frequency splittings of dipolar mixed modes: A window on the topology of deep magnetic fields. Astronomy and Astrophysics. 676, L9.","mla":"Mathis, S., and Lisa Annabelle Bugnet. “Asymmetries of Frequency Splittings of Dipolar Mixed Modes: A Window on the Topology of Deep Magnetic Fields.” <i>Astronomy and Astrophysics</i>, vol. 676, L9, EDP Sciences, 2023, doi:<a href=\"https://doi.org/10.1051/0004-6361/202346832\">10.1051/0004-6361/202346832</a>.","apa":"Mathis, S., &#38; Bugnet, L. A. (2023). Asymmetries of frequency splittings of dipolar mixed modes: A window on the topology of deep magnetic fields. <i>Astronomy and Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202346832\">https://doi.org/10.1051/0004-6361/202346832</a>"},"language":[{"iso":"eng"}],"oa":1,"type":"journal_article","date_updated":"2023-09-06T11:05:58Z","_id":"14256","publisher":"EDP Sciences","doi":"10.1051/0004-6361/202346832","article_processing_charge":"Yes (in subscription journal)","quality_controlled":"1","ddc":["520"],"external_id":{"isi":["001046037700007"],"arxiv":["2306.11587"]},"isi":1,"year":"2023","acknowledgement":"The authors are grateful to the referee for her/his detailed and constructive report, which has allowed us to improve our article. S. M. acknowledges support from the CNES GOLF-SOHO and PLATO grants at CEA/DAp and PNPS (CNRS/INSU). We thank R. A. Garcia for fruitful discussions and suggestions.","date_published":"2023-08-01T00:00:00Z","status":"public","publication":"Astronomy and Astrophysics"},{"publication":"Nature Astronomy","extern":"1","language":[{"iso":"eng"}],"status":"public","citation":{"ieee":"L. A. Bugnet, “Hidden currents at the Sun’s surface,” <i>Nature Astronomy</i>, vol. 6. Springer Nature, pp. 631–632, 2022.","short":"L.A. Bugnet, Nature Astronomy 6 (2022) 631–632.","ama":"Bugnet LA. Hidden currents at the Sun’s surface. <i>Nature Astronomy</i>. 2022;6:631-632. doi:<a href=\"https://doi.org/10.1038/s41550-022-01683-2\">10.1038/s41550-022-01683-2</a>","apa":"Bugnet, L. A. (2022). Hidden currents at the Sun’s surface. <i>Nature Astronomy</i>. Springer Nature. <a href=\"https://doi.org/10.1038/s41550-022-01683-2\">https://doi.org/10.1038/s41550-022-01683-2</a>","mla":"Bugnet, Lisa Annabelle. “Hidden Currents at the Sun’s Surface.” <i>Nature Astronomy</i>, vol. 6, Springer Nature, 2022, pp. 631–32, doi:<a href=\"https://doi.org/10.1038/s41550-022-01683-2\">10.1038/s41550-022-01683-2</a>.","chicago":"Bugnet, Lisa Annabelle. “Hidden Currents at the Sun’s Surface.” <i>Nature Astronomy</i>. Springer Nature, 2022. <a href=\"https://doi.org/10.1038/s41550-022-01683-2\">https://doi.org/10.1038/s41550-022-01683-2</a>.","ista":"Bugnet LA. 2022. Hidden currents at the Sun’s surface. Nature Astronomy. 6, 631–632."},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","date_published":"2022-05-18T00:00:00Z","year":"2022","month":"05","keyword":["Astronomy and Astrophysics"],"page":"631-632","intvolume":"         6","abstract":[{"lang":"eng","text":"The Sun’s surface hosts varying magnetic activities and rotation rates (from equator to pole), and unique solar weather. Now, a combination of ground and space observations has unveiled a previously undetected magnetized plasma current."}],"quality_controlled":"1","publication_status":"published","publication_identifier":{"eissn":["2397-3366"]},"scopus_import":"1","article_processing_charge":"No","day":"18","doi":"10.1038/s41550-022-01683-2","author":[{"first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle","last_name":"Bugnet"}],"publisher":"Springer Nature","oa_version":"None","title":"Hidden currents at the Sun’s surface","volume":6,"_id":"11600","date_updated":"2022-08-19T09:52:21Z","date_created":"2022-07-18T09:34:37Z","article_type":"letter_note","type":"journal_article"},{"main_file_link":[{"url":"https://arxiv.org/abs/2108.05455","open_access":"1"}],"quality_controlled":"1","article_processing_charge":"No","doi":"10.3847/1538-4357/ac2c83","publisher":"IOP Publishing","_id":"11601","date_updated":"2022-08-19T09:52:08Z","type":"journal_article","publication":"The Astrophysical Journal","status":"public","extern":"1","date_published":"2022-02-24T00:00:00Z","acknowledgement":"We would like to thank the anonymous referee whose comments significantly improved the manuscript. J.C.Z. is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-2001869. J.C.Z. and M.H.P. acknowledge support from NASA grants 80NSSC18K0391 and NNX17AJ40G. Y.E. and C.J. acknowledge the support of the UK Science and Technology Facilities Council (STFC). S.M. acknowledges support from the Spanish Ministry of Science and Innovation with the Ramon y Cajal fellowship number RYC-2015-17697 and the grant number PID2019-107187GB-I00. R.A.G. acknowledges funding received from the PLATO CNES grant. C.K. acknowledges funding from the UK Science and Technology Facilities Council (STFC) through grants ST/M000958/1, ST/R000905/1, and ST/V000632/1.\r\n\r\nFunding for the Stellar Astrophysics Centre (SAC) is provided by the Danish National Research Foundation (grant agreement No. DNRF106).\r\n\r\nThe K2 Galactic Archaeology Program is supported by the National Aeronautics and Space Administration under grant NNX16AJ17G issued through the K2 Guest Observer Program. This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation.\r\n\r\nThis paper includes data collected by the Kepler mission. Funding for the Kepler mission is provided by the NASA Science Mission directorate.\r\n\r\nParts of this research were supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013.\r\n\r\nThis research was partially conducted during the Exostar19 program at the Kavli Institute for Theoretical Physics at UC Santa Barbara, which was supported in part by the National Science Foundation under grant No. NSF PHY-1748958.\r\n\r\nBased in part on data obtained at Siding Spring Observatory via GALAH. We acknowledge the traditional owners of the land on which the AAT stands, the Gamilaraay people, and pay our respects to elders past and present.\r\n\r\nThis work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.\r\n\r\nFunding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS-IV acknowledges support and resources from the Center for High-Performance Computing at the University of Utah (www.sdss.org).\r\n\r\nSoftware: asfgrid (Sharma & Stello 2016), corner (Foreman-Mackey 2016), emcee (Foreman-Mackey et al. 2013), NumPy (Walt 2011), pandas (McKinney 2010), Matplotlib (Hunter 2007), IPython (Pérez & Granger 2007), SciPy (Virtanen et al.2020).","year":"2022","external_id":{"arxiv":["2108.05455"]},"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"intvolume":"       926","abstract":[{"text":"We present the third and final data release of the K2 Galactic Archaeology Program (K2 GAP) for Campaigns C1–C8 and C10–C18. We provide asteroseismic radius and mass coefficients, κR and κM, for ∼19,000 red giant stars, which translate directly to radius and mass given a temperature. As such, K2 GAP DR3 represents the largest asteroseismic sample in the literature to date. K2 GAP DR3 stellar parameters are calibrated to be on an absolute parallactic scale based on Gaia DR2, with red giant branch and red clump evolutionary state classifications provided via a machine-learning approach. Combining these stellar parameters with GALAH DR3 spectroscopy, we determine asteroseismic ages with precisions of ∼20%–30% and compare age-abundance relations to Galactic chemical evolution models among both low- and high-α populations for α, light, iron-peak, and neutron-capture elements. We confirm recent indications in the literature of both increased Ba production at late Galactic times as well as significant contributions to r-process enrichment from prompt sources associated with, e.g., core-collapse supernovae. With an eye toward other Galactic archeology applications, we characterize K2 GAP DR3 uncertainties and completeness using injection tests, suggesting that K2 GAP DR3 is largely unbiased in mass/age, with uncertainties of 2.9% (stat.) ± 0.1% (syst.) and 6.7% (stat.) ± 0.3% (syst.) in κR and κM for red giant branch stars and 4.7% (stat.) ± 0.3% (syst.) and 11% (stat.) ± 0.9% (syst.) for red clump stars. We also identify percent-level asteroseismic systematics, which are likely related to the time baseline of the underlying data, and which therefore should be considered in TESS asteroseismic analysis.","lang":"eng"}],"publication_status":"published","publication_identifier":{"issn":["0004-637X"],"eissn":["1538-4357"]},"day":"24","scopus_import":"1","author":[{"first_name":"Joel C.","full_name":"Zinn, Joel C.","last_name":"Zinn"},{"last_name":"Stello","full_name":"Stello, Dennis","first_name":"Dennis"},{"full_name":"Elsworth, Yvonne","last_name":"Elsworth","first_name":"Yvonne"},{"full_name":"García, Rafael A.","last_name":"García","first_name":"Rafael A."},{"first_name":"Thomas","last_name":"Kallinger","full_name":"Kallinger, Thomas"},{"first_name":"Savita","full_name":"Mathur, Savita","last_name":"Mathur"},{"first_name":"Benoît","last_name":"Mosser","full_name":"Mosser, Benoît"},{"last_name":"Hon","full_name":"Hon, Marc","first_name":"Marc"},{"last_name":"Bugnet","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle","first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000"},{"first_name":"Caitlin","full_name":"Jones, Caitlin","last_name":"Jones"},{"first_name":"Claudia","last_name":"Reyes","full_name":"Reyes, Claudia"},{"last_name":"Sharma","full_name":"Sharma, Sanjib","first_name":"Sanjib"},{"full_name":"Schönrich, Ralph","last_name":"Schönrich","first_name":"Ralph"},{"first_name":"Jack T.","full_name":"Warfield, Jack T.","last_name":"Warfield"},{"first_name":"Rodrigo","last_name":"Luger","full_name":"Luger, Rodrigo"},{"first_name":"Andrew","full_name":"Vanderburg, Andrew","last_name":"Vanderburg"},{"full_name":"Kobayashi, Chiaki","last_name":"Kobayashi","first_name":"Chiaki"},{"first_name":"Marc H.","last_name":"Pinsonneault","full_name":"Pinsonneault, Marc H."},{"full_name":"Johnson, Jennifer A.","last_name":"Johnson","first_name":"Jennifer A."},{"full_name":"Huber, Daniel","last_name":"Huber","first_name":"Daniel"},{"full_name":"Buder, Sven","last_name":"Buder","first_name":"Sven"},{"full_name":"Joyce, Meridith","last_name":"Joyce","first_name":"Meridith"},{"last_name":"Bland-Hawthorn","full_name":"Bland-Hawthorn, Joss","first_name":"Joss"},{"full_name":"Casagrande, Luca","last_name":"Casagrande","first_name":"Luca"},{"first_name":"Geraint F.","last_name":"Lewis","full_name":"Lewis, Geraint F."},{"last_name":"Miglio","full_name":"Miglio, Andrea","first_name":"Andrea"},{"first_name":"Thomas","last_name":"Nordlander","full_name":"Nordlander, Thomas"},{"last_name":"Davies","full_name":"Davies, Guy R.","first_name":"Guy R."},{"full_name":"Silva, Gayandhi De","last_name":"Silva","first_name":"Gayandhi De"},{"full_name":"Chaplin, William J.","last_name":"Chaplin","first_name":"William J."},{"first_name":"Victor","full_name":"Silva Aguirre, Victor","last_name":"Silva Aguirre"}],"oa_version":"Preprint","title":"The K2 Galactic Archaeology Program data release 3: Age-abundance patterns in C1–C8 and C10–C18","volume":926,"date_created":"2022-07-18T10:57:30Z","article_type":"original","oa":1,"language":[{"iso":"eng"}],"citation":{"ama":"Zinn JC, Stello D, Elsworth Y, et al. The K2 Galactic Archaeology Program data release 3: Age-abundance patterns in C1–C8 and C10–C18. <i>The Astrophysical Journal</i>. 2022;926(2). doi:<a href=\"https://doi.org/10.3847/1538-4357/ac2c83\">10.3847/1538-4357/ac2c83</a>","short":"J.C. Zinn, D. Stello, Y. Elsworth, R.A. García, T. Kallinger, S. Mathur, B. Mosser, M. Hon, L.A. Bugnet, C. Jones, C. Reyes, S. Sharma, R. Schönrich, J.T. Warfield, R. Luger, A. Vanderburg, C. Kobayashi, M.H. Pinsonneault, J.A. Johnson, D. Huber, S. Buder, M. Joyce, J. Bland-Hawthorn, L. Casagrande, G.F. Lewis, A. Miglio, T. Nordlander, G.R. Davies, G.D. Silva, W.J. Chaplin, V. Silva Aguirre, The Astrophysical Journal 926 (2022).","ieee":"J. C. Zinn <i>et al.</i>, “The K2 Galactic Archaeology Program data release 3: Age-abundance patterns in C1–C8 and C10–C18,” <i>The Astrophysical Journal</i>, vol. 926, no. 2. IOP Publishing, 2022.","ista":"Zinn JC, Stello D, Elsworth Y, García RA, Kallinger T, Mathur S, Mosser B, Hon M, Bugnet LA, Jones C, Reyes C, Sharma S, Schönrich R, Warfield JT, Luger R, Vanderburg A, Kobayashi C, Pinsonneault MH, Johnson JA, Huber D, Buder S, Joyce M, Bland-Hawthorn J, Casagrande L, Lewis GF, Miglio A, Nordlander T, Davies GR, Silva GD, Chaplin WJ, Silva Aguirre V. 2022. The K2 Galactic Archaeology Program data release 3: Age-abundance patterns in C1–C8 and C10–C18. The Astrophysical Journal. 926(2), 191.","chicago":"Zinn, Joel C., Dennis Stello, Yvonne Elsworth, Rafael A. García, Thomas Kallinger, Savita Mathur, Benoît Mosser, et al. “The K2 Galactic Archaeology Program Data Release 3: Age-Abundance Patterns in C1–C8 and C10–C18.” <i>The Astrophysical Journal</i>. IOP Publishing, 2022. <a href=\"https://doi.org/10.3847/1538-4357/ac2c83\">https://doi.org/10.3847/1538-4357/ac2c83</a>.","mla":"Zinn, Joel C., et al. “The K2 Galactic Archaeology Program Data Release 3: Age-Abundance Patterns in C1–C8 and C10–C18.” <i>The Astrophysical Journal</i>, vol. 926, no. 2, 191, IOP Publishing, 2022, doi:<a href=\"https://doi.org/10.3847/1538-4357/ac2c83\">10.3847/1538-4357/ac2c83</a>.","apa":"Zinn, J. C., Stello, D., Elsworth, Y., García, R. A., Kallinger, T., Mathur, S., … Silva Aguirre, V. (2022). The K2 Galactic Archaeology Program data release 3: Age-abundance patterns in C1–C8 and C10–C18. <i>The Astrophysical Journal</i>. IOP Publishing. <a href=\"https://doi.org/10.3847/1538-4357/ac2c83\">https://doi.org/10.3847/1538-4357/ac2c83</a>"},"issue":"2","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","month":"02","arxiv":1,"article_number":"191"},{"acknowledgement":"This paper includes data collected by the Kepler mission. Funding for the Kepler mission is provided by the NASA Science Mission directorate. Some of the data presented in this paper were obtained from the Mikulski Archive for Space Telescopes (MAST). STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. S. M. acknowledges support by the Spanish Ministry of Science and Innovation with the Ramon y Cajal fellowship number RYC-2015-17697 and the grant number PID2019-107187GB-I00. R. A. G. and S. N. B acknowledge the support from PLATO and GOLF CNES grants. A. R. G. S. acknowledges the support from National Aeronautics and Space Administration under Grant NNX17AF27G and STFC consolidated grant ST/T000252/1. D.H. acknowledges support from the Alfred P. Sloan Foundation, the National Aeronautics and Space Administration (80NSSC19K0597), and the National Science Foundation (AST-1717000). M.S. is supported by the Research Corporation for Science Advancement through Scialog award #26080. Guoshoujing Telescope (the Large Sky Area Multi-Object Fiber Spectroscopic Telescope LAMOST) is a National Major Scientific Project built by the Chinese Academy of Sciences. Funding for the project has been provided by the National Development and Reform Commission. LAMOST is operated and managed by the National Astronomical Observatories, Chinese Academy of Sciences.","date_published":"2022-01-01T00:00:00Z","extern":"1","status":"public","publication":"Astronomy & Astrophysics","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"year":"2022","external_id":{"arxiv":["2109.14058"]},"main_file_link":[{"url":"https://arxiv.org/abs/2109.14058","open_access":"1"}],"quality_controlled":"1","_id":"11602","date_updated":"2022-08-19T09:56:58Z","type":"journal_article","article_processing_charge":"No","doi":"10.1051/0004-6361/202141168","publisher":"EDP Sciences","citation":{"mla":"Mathur, S., et al. “Detections of Solar-like Oscillations in Dwarfs and Subgiants with Kepler DR25 Short-Cadence Data.” <i>Astronomy &#38; Astrophysics</i>, vol. 657, A31, EDP Sciences, 2022, doi:<a href=\"https://doi.org/10.1051/0004-6361/202141168\">10.1051/0004-6361/202141168</a>.","apa":"Mathur, S., García, R. A., Breton, S., Santos, A. R. G., Mosser, B., Huber, D., … Chontos, A. (2022). Detections of solar-like oscillations in dwarfs and subgiants with Kepler DR25 short-cadence data. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202141168\">https://doi.org/10.1051/0004-6361/202141168</a>","chicago":"Mathur, S., R. A. García, S. Breton, A. R. G. Santos, B. Mosser, D. Huber, M. Sayeed, Lisa Annabelle Bugnet, and A. Chontos. “Detections of Solar-like Oscillations in Dwarfs and Subgiants with Kepler DR25 Short-Cadence Data.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2022. <a href=\"https://doi.org/10.1051/0004-6361/202141168\">https://doi.org/10.1051/0004-6361/202141168</a>.","ista":"Mathur S, García RA, Breton S, Santos ARG, Mosser B, Huber D, Sayeed M, Bugnet LA, Chontos A. 2022. Detections of solar-like oscillations in dwarfs and subgiants with Kepler DR25 short-cadence data. Astronomy &#38; Astrophysics. 657, A31.","short":"S. Mathur, R.A. García, S. Breton, A.R.G. Santos, B. Mosser, D. Huber, M. Sayeed, L.A. Bugnet, A. Chontos, Astronomy &#38; Astrophysics 657 (2022).","ieee":"S. Mathur <i>et al.</i>, “Detections of solar-like oscillations in dwarfs and subgiants with Kepler DR25 short-cadence data,” <i>Astronomy &#38; Astrophysics</i>, vol. 657. EDP Sciences, 2022.","ama":"Mathur S, García RA, Breton S, et al. Detections of solar-like oscillations in dwarfs and subgiants with Kepler DR25 short-cadence data. <i>Astronomy &#38; Astrophysics</i>. 2022;657. doi:<a href=\"https://doi.org/10.1051/0004-6361/202141168\">10.1051/0004-6361/202141168</a>"},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","oa":1,"language":[{"iso":"eng"}],"article_number":"A31","arxiv":1,"month":"01","publication_status":"published","publication_identifier":{"issn":["0004-6361"],"eissn":["1432-0746"]},"abstract":[{"lang":"eng","text":"During the survey phase of the Kepler mission, several thousand stars were observed in short cadence, allowing for the detection of solar-like oscillations in more than 500 main-sequence and subgiant stars. These detections showed the power of asteroseismology in determining fundamental stellar parameters. However, the Kepler Science Office discovered an issue in the calibration that affected half of the store of short-cadence data, leading to a new data release (DR25) with corrections on the light curves. In this work, we re-analyzed the one-month time series of the Kepler survey phase to search for solar-like oscillations that might have been missed when using the previous data release. We studied the seismic parameters of 99 stars, among which there are 46 targets with new reported solar-like oscillations, increasing, by around 8%, the known sample of solar-like stars with an asteroseismic analysis of the short-cadence data from this mission. The majority of these stars have mid- to high-resolution spectroscopy publicly available with the LAMOST and APOGEE surveys, respectively, as well as precise Gaia parallaxes. We computed the masses and radii using seismic scaling relations and we find that this new sample features massive stars (above 1.2 M⊙ and up to 2 M⊙) and subgiants. We determined the granulation parameters and amplitude of the modes, which agree with the scaling relations derived for dwarfs and subgiants. The stars studied here are slightly fainter than the previously known sample of main-sequence and subgiants with asteroseismic detections. We also studied the surface rotation and magnetic activity levels of those stars. Our sample of 99 stars has similar levels of activity compared to the previously known sample and is in the same range as the Sun between the minimum and maximum of its activity cycle. We find that for seven stars, a possible blend could be the reason for the non-detection with the early data release. Finally, we compared the radii obtained from the scaling relations with the Gaia ones and we find that the Gaia radii are overestimated by 4.4%, on average, compared to the seismic radii, with a scatter of 12.3% and a decreasing trend according to the evolutionary stage. In addition, for homogeneity purposes, we re-analyzed the DR25 of the main-sequence and subgiant stars with solar-like oscillations that were previously detected and, as a result, we provide the global seismic parameters for a total of 525 stars."}],"intvolume":"       657","volume":657,"date_created":"2022-07-18T11:41:59Z","article_type":"original","day":"01","scopus_import":"1","author":[{"last_name":"Mathur","full_name":"Mathur, S.","first_name":"S."},{"full_name":"García, R. A.","last_name":"García","first_name":"R. A."},{"first_name":"S.","last_name":"Breton","full_name":"Breton, S."},{"first_name":"A. R. G.","last_name":"Santos","full_name":"Santos, A. R. G."},{"last_name":"Mosser","full_name":"Mosser, B.","first_name":"B."},{"full_name":"Huber, D.","last_name":"Huber","first_name":"D."},{"first_name":"M.","full_name":"Sayeed, M.","last_name":"Sayeed"},{"orcid":"0000-0003-0142-4000","first_name":"Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle","last_name":"Bugnet"},{"first_name":"A.","full_name":"Chontos, A.","last_name":"Chontos"}],"title":"Detections of solar-like oscillations in dwarfs and subgiants with Kepler DR25 short-cadence data","oa_version":"Preprint"},{"month":"05","arxiv":1,"article_number":"A133","language":[{"iso":"eng"}],"oa":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","citation":{"short":"H. Dhouib, S. Mathis, L.A. Bugnet, T. Van Reeth, C. Aerts, Astronomy &#38; Astrophysics 661 (2022).","ieee":"H. Dhouib, S. Mathis, L. A. Bugnet, T. Van Reeth, and C. Aerts, “Detecting deep axisymmetric toroidal magnetic fields in stars: The traditional approximation of rotation for differentially rotating deep spherical shells with a general azimuthal magnetic field,” <i>Astronomy &#38; Astrophysics</i>, vol. 661. EDP Sciences, 2022.","ama":"Dhouib H, Mathis S, Bugnet LA, Van Reeth T, Aerts C. Detecting deep axisymmetric toroidal magnetic fields in stars: The traditional approximation of rotation for differentially rotating deep spherical shells with a general azimuthal magnetic field. <i>Astronomy &#38; Astrophysics</i>. 2022;661. doi:<a href=\"https://doi.org/10.1051/0004-6361/202142956\">10.1051/0004-6361/202142956</a>","mla":"Dhouib, H., et al. “Detecting Deep Axisymmetric Toroidal Magnetic Fields in Stars: The Traditional Approximation of Rotation for Differentially Rotating Deep Spherical Shells with a General Azimuthal Magnetic Field.” <i>Astronomy &#38; Astrophysics</i>, vol. 661, A133, EDP Sciences, 2022, doi:<a href=\"https://doi.org/10.1051/0004-6361/202142956\">10.1051/0004-6361/202142956</a>.","apa":"Dhouib, H., Mathis, S., Bugnet, L. A., Van Reeth, T., &#38; Aerts, C. (2022). Detecting deep axisymmetric toroidal magnetic fields in stars: The traditional approximation of rotation for differentially rotating deep spherical shells with a general azimuthal magnetic field. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202142956\">https://doi.org/10.1051/0004-6361/202142956</a>","chicago":"Dhouib, H., S. Mathis, Lisa Annabelle Bugnet, T. Van Reeth, and C. Aerts. “Detecting Deep Axisymmetric Toroidal Magnetic Fields in Stars: The Traditional Approximation of Rotation for Differentially Rotating Deep Spherical Shells with a General Azimuthal Magnetic Field.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2022. <a href=\"https://doi.org/10.1051/0004-6361/202142956\">https://doi.org/10.1051/0004-6361/202142956</a>.","ista":"Dhouib H, Mathis S, Bugnet LA, Van Reeth T, Aerts C. 2022. Detecting deep axisymmetric toroidal magnetic fields in stars: The traditional approximation of rotation for differentially rotating deep spherical shells with a general azimuthal magnetic field. Astronomy &#38; Astrophysics. 661, A133."},"title":"Detecting deep axisymmetric toroidal magnetic fields in stars: The traditional approximation of rotation for differentially rotating deep spherical shells with a general azimuthal magnetic field","oa_version":"Preprint","author":[{"full_name":"Dhouib, H.","last_name":"Dhouib","first_name":"H."},{"last_name":"Mathis","full_name":"Mathis, S.","first_name":"S."},{"orcid":"0000-0003-0142-4000","first_name":"Lisa Annabelle","full_name":"Bugnet, Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501","last_name":"Bugnet"},{"full_name":"Van Reeth, T.","last_name":"Van Reeth","first_name":"T."},{"first_name":"C.","last_name":"Aerts","full_name":"Aerts, C."}],"scopus_import":"1","day":"19","article_type":"original","date_created":"2022-07-19T08:04:15Z","volume":661,"abstract":[{"text":"Context. Asteroseismology has revealed small core-to-surface rotation contrasts in stars in the whole Hertzsprung–Russell diagram. This is the signature of strong transport of angular momentum (AM) in stellar interiors. One of the plausible candidates to efficiently carry AM is magnetic fields with various topologies that could be present in stellar radiative zones. Among them, strong axisymmetric azimuthal (toroidal) magnetic fields have received a lot of interest. Indeed, if they are subject to the so-called Tayler instability, the accompanying triggered Maxwell stresses can transport AM efficiently. In addition, the electromotive force induced by the fluctuations of magnetic and velocity fields could potentially sustain a dynamo action that leads to the regeneration of the initial strong axisymmetric azimuthal magnetic field.\r\n\r\nAims. The key question we aim to answer is whether we can detect signatures of these deep strong azimuthal magnetic fields. The only way to answer this question is asteroseismology, and the best laboratories of study are intermediate-mass and massive stars with external radiative envelopes. Most of these are rapid rotators during their main sequence. Therefore, we have to study stellar pulsations propagating in stably stratified, rotating, and potentially strongly magnetised radiative zones, namely magneto-gravito-inertial (MGI) waves.\r\n\r\nMethods. We generalise the traditional approximation of rotation (TAR) by simultaneously taking general axisymmetric differential rotation and azimuthal magnetic fields into account. Both the Coriolis acceleration and the Lorentz force are therefore treated in a non-perturbative way. Using this new formalism, we derive the asymptotic properties of MGI waves and their period spacings.\r\n\r\nResults. We find that toroidal magnetic fields induce a shift in the period spacings of gravity (g) and Rossby (r) modes. An equatorial azimuthal magnetic field with an amplitude of the order of 105 G leads to signatures that are detectable in period spacings for high-radial-order g and r modes in γ Doradus (γ Dor) and slowly pulsating B (SPB) stars. More complex hemispheric configurations are more difficult to observe, particularly when they are localised out of the propagation region of MGI modes, which can be localised in an equatorial belt.\r\n\r\nConclusions. The magnetic TAR, which takes into account toroidal magnetic fields in a non-perturbative way, is derived. This new formalism allows us to assess the effects of the magnetic field in γ Dor and SPB stars on g and r modes. We find that these effects should be detectable for equatorial fields thanks to modern space photometry using observations from Kepler, TESS CVZ, and PLATO.","lang":"eng"}],"intvolume":"       661","publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"publication_status":"published","external_id":{"arxiv":["2202.10026"]},"year":"2022","keyword":["Space and Planetary Science","Astronomy and Astrophysics","magnetohydrodynamics (MHD) / waves / stars","rotation / stars: magnetic field / stars","oscillations / methods"],"extern":"1","publication":"Astronomy & Astrophysics","status":"public","date_published":"2022-05-19T00:00:00Z","acknowledgement":"We thank the referee for her/his positive and constructive report, which has allowed us to improve the quality of our article. H.D. and S.M. acknowledge support from the CNES PLATO grant at CEA/DAp. T.V.R. gratefully acknowledges support from the Research Foundation Flanders (FWO) under grant agreement No. 12ZB620N and V414021N. This research was supported in part by the National Science Foundation under Grant No. NSF PHY-1748958. C.A. is supported by the KU Leuven Research Council (grant C16/18/005: PARADISE) as well as from the BELgian federal Science Policy Office (BELSPO) through a PLATO PRODEX grant.","publisher":"EDP Sciences","doi":"10.1051/0004-6361/202142956","article_processing_charge":"No","type":"journal_article","date_updated":"2022-08-22T07:58:54Z","_id":"11621","quality_controlled":"1","main_file_link":[{"url":"https://arxiv.org/abs/2202.10026","open_access":"1"}]},{"citation":{"ieee":"J. M. J. Ong, L. A. Bugnet, and S. Basu, “Mode mixing and rotational splittings. I. Near-degeneracy effects revisited,” <i>The Astrophysical Journal</i>, vol. 940, no. 1. American Astronomical Society, 2022.","short":"J.M.J. Ong, L.A. Bugnet, S. Basu, The Astrophysical Journal 940 (2022).","ama":"Ong JMJ, Bugnet LA, Basu S. Mode mixing and rotational splittings. I. Near-degeneracy effects revisited. <i>The Astrophysical Journal</i>. 2022;940(1). doi:<a href=\"https://doi.org/10.3847/1538-4357/ac97e7\">10.3847/1538-4357/ac97e7</a>","apa":"Ong, J. M. J., Bugnet, L. A., &#38; Basu, S. (2022). Mode mixing and rotational splittings. I. Near-degeneracy effects revisited. <i>The Astrophysical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-4357/ac97e7\">https://doi.org/10.3847/1538-4357/ac97e7</a>","mla":"Ong, J. M. Joel, et al. “Mode Mixing and Rotational Splittings. I. Near-Degeneracy Effects Revisited.” <i>The Astrophysical Journal</i>, vol. 940, no. 1, 18, American Astronomical Society, 2022, doi:<a href=\"https://doi.org/10.3847/1538-4357/ac97e7\">10.3847/1538-4357/ac97e7</a>.","ista":"Ong JMJ, Bugnet LA, Basu S. 2022. Mode mixing and rotational splittings. I. Near-degeneracy effects revisited. The Astrophysical Journal. 940(1), 18.","chicago":"Ong, J. M. Joel, Lisa Annabelle Bugnet, and Sarbani Basu. “Mode Mixing and Rotational Splittings. I. Near-Degeneracy Effects Revisited.” <i>The Astrophysical Journal</i>. American Astronomical Society, 2022. <a href=\"https://doi.org/10.3847/1538-4357/ac97e7\">https://doi.org/10.3847/1538-4357/ac97e7</a>."},"issue":"1","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","oa":1,"language":[{"iso":"eng"}],"article_number":"18","month":"11","arxiv":1,"publication_status":"published","publication_identifier":{"eissn":["1538-4357"],"issn":["0004-637X"]},"abstract":[{"text":"Rotation is typically assumed to induce strictly symmetric rotational splitting into the rotational multiplets of pure p- and g-modes. However, for evolved stars exhibiting mixed modes, avoided crossings between different multiplet components are known to yield asymmetric rotational splitting, in particular for near-degenerate mixed-mode pairs, where notional pure p-modes are fortuitously in resonance with pure g-modes. These near-degeneracy effects have been described in subgiants, but their consequences for the characterization of internal rotation in red giants have not previously been investigated in detail, in part owing to theoretical intractability. We employ new developments in the analytic theory of mixed-mode coupling to study these near-resonance phenomena. In the vicinity of the most p-dominated mixed modes, the near-degenerate intrinsic asymmetry from pure rotational splitting increases dramatically over the course of stellar evolution, and it depends strongly on the mode-mixing fraction ζ. We also find that a linear treatment of rotation remains viable for describing the underlying p- and g-modes, even when it does not for the resulting mixed modes undergoing these avoided crossings. We explore observational consequences for potential measurements of asymmetric mixed-mode splitting, which has been proposed as a magnetic-field diagnostic. Finally, we propose improved measurement techniques for rotational characterization, exploiting the linearity of rotational effects on the underlying p/g-modes, while still accounting for these mixed-mode coupling effects.","lang":"eng"}],"intvolume":"       940","volume":940,"date_created":"2023-08-01T14:20:41Z","article_type":"original","scopus_import":"1","day":"16","author":[{"full_name":"Ong, J. M. Joel","last_name":"Ong","first_name":"J. M. Joel"},{"last_name":"Bugnet","full_name":"Bugnet, Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501","first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000"},{"full_name":"Basu, Sarbani","last_name":"Basu","first_name":"Sarbani"}],"oa_version":"Published Version","title":"Mode mixing and rotational splittings. I. Near-degeneracy effects revisited","date_published":"2022-11-16T00:00:00Z","extern":"1","publication":"The Astrophysical Journal","status":"public","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"year":"2022","external_id":{"arxiv":["2210.01928"]},"main_file_link":[{"url":"https://arxiv.org/abs/2210.01928","open_access":"1"}],"quality_controlled":"1","_id":"13445","date_updated":"2023-09-06T07:27:45Z","type":"journal_article","article_processing_charge":"No","doi":"10.3847/1538-4357/ac97e7","publisher":"American Astronomical Society"},{"main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2107.06301"}],"quality_controlled":"1","doi":"10.3847/1538-3881/ac166a","article_processing_charge":"No","publisher":"IOP Publishing","date_updated":"2022-08-19T10:01:56Z","_id":"11604","type":"journal_article","extern":"1","status":"public","publication":"The Astronomical Journal","acknowledgement":"The research leading to these results has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 670519: MAMSIE), from the KU Leuven Research Council (grant C16/18/005: PARADISE), from the Research Foundation Flanders (FWO) under grant agreement G0H5416N (ERC Runner Up Project), as well as from the BELgian federal Science Policy Office (BELSPO) through PRODEX grant PLATO. D.J.A acknowledges support from the STFC via an Ernest Rutherford Fellowship (ST/R00384X/1). Funding for the Stellar Astrophysics Centre is provided by The Danish National Research Foundation (grant agreement No.: DNRF106). R.H. and M.N.L. acknowledge the ESA PRODEX program. This research was supported by the National Aeronautics and Space Administration (80NSSC18K1585 and 80NSSC19K0379) awarded through the TESS Guest Investigator Program. K.J.B. is supported by the National Science Foundation under Award AST-1903828. J.S.K and K.J.B. were supported by funding from the European Research Council under the European Community's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement no. 338251 (StellarAges). D.M.B. gratefully acknowledges funding from a senior postdoctoral fellowship from the Research Foundation Flanders (FWO) with grant agreement No. 1286521N. The research leading to these results has received funding from the Research Foundation Flanders (FWO) under grant agreement G0A2917N (BlackGEM). R.A.G. acknowledges support from the GOLF and PLATO CNES grants. L.M. was supported by the Premium Postdoctoral Research Program of the Hungarian Academy of Sciences. The research leading to these results has been supported by the Hungarian National Research, Development, and Innovation Office (NKFIH) grant KH_18 130405 and the Lendület LP2014-17 and LP2018-7/2020 grants of the Hungarian Academy of Sciences. D.B. acknowledges support from the NASA TESS Guest Investigator Program under award 80NSSC19K0385.\r\n\r\nThis paper includes data collected by the TESS mission, which are publicly available from the Mikulski Archive for Space Telescopes (MAST). Funding for the TESS mission is provided by NASA's Science Mission directorate. This research has made use of NASA's Astrophysics Data System as well as the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. Funding for the TESS Asteroseismic Science Operations Centre is provided by the Danish National Research Foundation (Grant agreement no.: DNRF106), ESA PRODEX (PEA 4000119301), and the Stellar Astrophysics Centre (SAC) at Aarhus University. We thank the TESS team and staff and TASC/TASOC for their support of the present work.\r\n\r\nThis paper includes data collected by the Kepler mission. Funding for the Kepler and K2 mission was provided by NASA's Science Mission Directorate. The authors acknowledge the efforts of the Kepler Mission team in obtaining the light-curve data and data validation products used in this publication. These data were generated by the Kepler Mission science pipeline through the efforts of the Kepler Science Operations Center and Science Office. The Kepler light curves are archived at the Mikulski Archive for Space Telescopes.\r\n\r\nThe numerical results presented in this work were obtained at the Centre for Scientific Computing, Aarhus. 37 This research made use of Astropy, a community-developed core Python package for Astronomy (Astropy Collaboration et al. 2013, 2018).\r\n\r\nSoftware: Scikit-learn (Pedregosa et al. 2011), Numpy (Harris et al. 2020), Astropy (Astropy Collaboration et al. 2013, 2018), Scipy (Virtanen et al. 2020), Pandas (McKinney 2010; Pandas Development Team 2020), Lightkurve (Lightkurve Collaboration et al. 2018), XGBoost (Chen & Guestrin 2016), Tensorflow (Abadi et al. 2015).","date_published":"2021-10-21T00:00:00Z","year":"2021","external_id":{"arxiv":["2107.06301"]},"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"intvolume":"       162","abstract":[{"text":"The NASA Transiting Exoplanet Survey Satellite (TESS) is observing tens of millions of stars with time spans ranging from ∼27 days to about 1 yr of continuous observations. This vast amount of data contains a wealth of information for variability, exoplanet, and stellar astrophysics studies but requires a number of processing steps before it can be fully utilized. In order to efficiently process all the TESS data and make it available to the wider scientific community, the TESS Data for Asteroseismology working group, as part of the TESS Asteroseismic Science Consortium, has created an automated open-source processing pipeline to produce light curves corrected for systematics from the short- and long-cadence raw photometry data and to classify these according to stellar variability type. We will process all stars down to a TESS magnitude of 15. This paper is the next in a series detailing how the pipeline works. Here, we present our methodology for the automatic variability classification of TESS photometry using an ensemble of supervised learners that are combined into a metaclassifier. We successfully validate our method using a carefully constructed labeled sample of Kepler Q9 light curves with a 27.4 days time span mimicking single-sector TESS observations, on which we obtain an overall accuracy of 94.9%. We demonstrate that our methodology can successfully classify stars outside of our labeled sample by applying it to all ∼167,000 stars observed in Q9 of the Kepler space mission.","lang":"eng"}],"publication_identifier":{"eissn":["1538-3881"],"issn":["0004-6256"]},"publication_status":"published","author":[{"first_name":"J.","last_name":"Audenaert","full_name":"Audenaert, J."},{"first_name":"J. S.","last_name":"Kuszlewicz","full_name":"Kuszlewicz, J. S."},{"last_name":"Handberg","full_name":"Handberg, R.","first_name":"R."},{"full_name":"Tkachenko, A.","last_name":"Tkachenko","first_name":"A."},{"first_name":"D. J.","last_name":"Armstrong","full_name":"Armstrong, D. J."},{"last_name":"Hon","full_name":"Hon, M.","first_name":"M."},{"first_name":"R.","last_name":"Kgoadi","full_name":"Kgoadi, R."},{"last_name":"Lund","full_name":"Lund, M. N.","first_name":"M. N."},{"first_name":"K. J.","full_name":"Bell, K. J.","last_name":"Bell"},{"orcid":"0000-0003-0142-4000","first_name":"Lisa Annabelle","last_name":"Bugnet","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle"},{"last_name":"Bowman","full_name":"Bowman, D. M.","first_name":"D. M."},{"last_name":"Johnston","full_name":"Johnston, C.","first_name":"C."},{"first_name":"R. A.","last_name":"García","full_name":"García, R. A."},{"first_name":"D.","last_name":"Stello","full_name":"Stello, D."},{"first_name":"L.","last_name":"Molnár","full_name":"Molnár, L."},{"first_name":"E.","full_name":"Plachy, E.","last_name":"Plachy"},{"first_name":"D.","full_name":"Buzasi, D.","last_name":"Buzasi"},{"first_name":"C.","last_name":"Aerts","full_name":"Aerts, C."}],"day":"21","scopus_import":"1","title":"TESS Data for Asteroseismology (T’DA) stellar variability classification pipeline: Setup and application to the Kepler Q9 data","oa_version":"Preprint","volume":162,"article_type":"original","date_created":"2022-07-18T11:54:55Z","oa":1,"language":[{"iso":"eng"}],"issue":"5","citation":{"ama":"Audenaert J, Kuszlewicz JS, Handberg R, et al. TESS Data for Asteroseismology (T’DA) stellar variability classification pipeline: Setup and application to the Kepler Q9 data. <i>The Astronomical Journal</i>. 2021;162(5). doi:<a href=\"https://doi.org/10.3847/1538-3881/ac166a\">10.3847/1538-3881/ac166a</a>","short":"J. Audenaert, J.S. Kuszlewicz, R. Handberg, A. Tkachenko, D.J. Armstrong, M. Hon, R. Kgoadi, M.N. Lund, K.J. Bell, L.A. Bugnet, D.M. Bowman, C. Johnston, R.A. García, D. Stello, L. Molnár, E. Plachy, D. Buzasi, C. Aerts, The Astronomical Journal 162 (2021).","ieee":"J. Audenaert <i>et al.</i>, “TESS Data for Asteroseismology (T’DA) stellar variability classification pipeline: Setup and application to the Kepler Q9 data,” <i>The Astronomical Journal</i>, vol. 162, no. 5. IOP Publishing, 2021.","ista":"Audenaert J, Kuszlewicz JS, Handberg R, Tkachenko A, Armstrong DJ, Hon M, Kgoadi R, Lund MN, Bell KJ, Bugnet LA, Bowman DM, Johnston C, García RA, Stello D, Molnár L, Plachy E, Buzasi D, Aerts C. 2021. TESS Data for Asteroseismology (T’DA) stellar variability classification pipeline: Setup and application to the Kepler Q9 data. The Astronomical Journal. 162(5), 209.","chicago":"Audenaert, J., J. S. Kuszlewicz, R. Handberg, A. Tkachenko, D. J. Armstrong, M. Hon, R. Kgoadi, et al. “TESS Data for Asteroseismology (T’DA) Stellar Variability Classification Pipeline: Setup and Application to the Kepler Q9 Data.” <i>The Astronomical Journal</i>. IOP Publishing, 2021. <a href=\"https://doi.org/10.3847/1538-3881/ac166a\">https://doi.org/10.3847/1538-3881/ac166a</a>.","mla":"Audenaert, J., et al. “TESS Data for Asteroseismology (T’DA) Stellar Variability Classification Pipeline: Setup and Application to the Kepler Q9 Data.” <i>The Astronomical Journal</i>, vol. 162, no. 5, 209, IOP Publishing, 2021, doi:<a href=\"https://doi.org/10.3847/1538-3881/ac166a\">10.3847/1538-3881/ac166a</a>.","apa":"Audenaert, J., Kuszlewicz, J. S., Handberg, R., Tkachenko, A., Armstrong, D. J., Hon, M., … Aerts, C. (2021). TESS Data for Asteroseismology (T’DA) stellar variability classification pipeline: Setup and application to the Kepler Q9 data. <i>The Astronomical Journal</i>. IOP Publishing. <a href=\"https://doi.org/10.3847/1538-3881/ac166a\">https://doi.org/10.3847/1538-3881/ac166a</a>"},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","month":"10","arxiv":1,"article_number":"209"},{"status":"public","extern":"1","publication":"Astronomy & Astrophysics","date_published":"2021-06-07T00:00:00Z","external_id":{"arxiv":["2102.01216"]},"year":"2021","keyword":["Space and Planetary Science","Astronomy and Astrophysics","stars","oscillations / stars","magnetic field / stars","interiors / stars","evolution / stars","rotation"],"quality_controlled":"1","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2102.01216"}],"publisher":"EDP Sciences","article_processing_charge":"No","doi":"10.1051/0004-6361/202039159","type":"journal_article","_id":"11605","date_updated":"2022-08-19T10:06:33Z","language":[{"iso":"eng"}],"oa":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","citation":{"apa":"Bugnet, L. A., Prat, V., Mathis, S., Astoul, A., Augustson, K., García, R. A., … Neiner, C. (2021). Magnetic signatures on mixed-mode frequencies: I. An axisymmetric fossil field inside the core of red giants. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202039159\">https://doi.org/10.1051/0004-6361/202039159</a>","mla":"Bugnet, Lisa Annabelle, et al. “Magnetic Signatures on Mixed-Mode Frequencies: I. An Axisymmetric Fossil Field inside the Core of Red Giants.” <i>Astronomy &#38; Astrophysics</i>, vol. 650, A53, EDP Sciences, 2021, doi:<a href=\"https://doi.org/10.1051/0004-6361/202039159\">10.1051/0004-6361/202039159</a>.","ista":"Bugnet LA, Prat V, Mathis S, Astoul A, Augustson K, García RA, Mathur S, Amard L, Neiner C. 2021. Magnetic signatures on mixed-mode frequencies: I. An axisymmetric fossil field inside the core of red giants. Astronomy &#38; Astrophysics. 650, A53.","chicago":"Bugnet, Lisa Annabelle, V. Prat, S. Mathis, A. Astoul, K. Augustson, R. A. García, S. Mathur, L. Amard, and C. Neiner. “Magnetic Signatures on Mixed-Mode Frequencies: I. An Axisymmetric Fossil Field inside the Core of Red Giants.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2021. <a href=\"https://doi.org/10.1051/0004-6361/202039159\">https://doi.org/10.1051/0004-6361/202039159</a>.","ieee":"L. A. Bugnet <i>et al.</i>, “Magnetic signatures on mixed-mode frequencies: I. An axisymmetric fossil field inside the core of red giants,” <i>Astronomy &#38; Astrophysics</i>, vol. 650. EDP Sciences, 2021.","short":"L.A. Bugnet, V. Prat, S. Mathis, A. Astoul, K. Augustson, R.A. García, S. Mathur, L. Amard, C. Neiner, Astronomy &#38; Astrophysics 650 (2021).","ama":"Bugnet LA, Prat V, Mathis S, et al. Magnetic signatures on mixed-mode frequencies: I. An axisymmetric fossil field inside the core of red giants. <i>Astronomy &#38; Astrophysics</i>. 2021;650. doi:<a href=\"https://doi.org/10.1051/0004-6361/202039159\">10.1051/0004-6361/202039159</a>"},"arxiv":1,"month":"06","article_number":"A53","intvolume":"       650","abstract":[{"text":"Context. The discovery of moderate differential rotation between the core and the envelope of evolved solar-like stars could be the signature of a strong magnetic field trapped inside the radiative interior. The population of intermediate-mass red giants presenting surprisingly low-amplitude mixed modes (i.e. oscillation modes that behave as acoustic modes in their external envelope and as gravity modes in their core) could also arise from the effect of an internal magnetic field. Indeed, stars more massive than about 1.1 solar masses are known to develop a convective core during their main sequence. The field generated by the dynamo triggered by this convection could be the progenitor of a strong fossil magnetic field trapped inside the core of the star for the remainder of its evolution.\r\n\r\nAims. Observations of mixed modes can constitute an excellent probe of the deepest layers of evolved solar-like stars, and magnetic fields in those regions can impact their propagation. The magnetic perturbation on mixed modes may therefore be visible in asteroseismic data. To unravel which constraints can be obtained from observations, we theoretically investigate the effects of a plausible mixed axisymmetric magnetic field with various amplitudes on the mixed-mode frequencies of evolved solar-like stars.\r\n\r\nMethods. First-order frequency perturbations due to an axisymmetric magnetic field were computed for dipolar and quadrupolar mixed modes. These computations were carried out for a range of stellar ages, masses, and metallicities.\r\n\r\nConclusions. We show that typical fossil-field strengths of 0.1 − 1 MG, consistent with the presence of a dynamo in the convective core during the main sequence, provoke significant asymmetries on mixed-mode frequency multiplets during the red giant branch. We provide constraints and methods for the detectability of such magnetic signatures. We show that these signatures may be detectable in asteroseismic data for field amplitudes small enough for the amplitude of the modes not to be affected by the conversion of gravity into Alfvén waves inside the magnetised interior. Finally, we infer an upper limit for the strength of the field and the associated lower limit for the timescale of its action in order to redistribute angular momentum in stellar interiors.","lang":"eng"}],"publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"publication_status":"published","oa_version":"Preprint","title":"Magnetic signatures on mixed-mode frequencies: I. An axisymmetric fossil field inside the core of red giants","scopus_import":"1","day":"07","author":[{"first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000","last_name":"Bugnet","full_name":"Bugnet, Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501"},{"first_name":"V.","full_name":"Prat, V.","last_name":"Prat"},{"last_name":"Mathis","full_name":"Mathis, S.","first_name":"S."},{"last_name":"Astoul","full_name":"Astoul, A.","first_name":"A."},{"first_name":"K.","full_name":"Augustson, K.","last_name":"Augustson"},{"first_name":"R. A.","full_name":"García, R. A.","last_name":"García"},{"first_name":"S.","full_name":"Mathur, S.","last_name":"Mathur"},{"first_name":"L.","full_name":"Amard, L.","last_name":"Amard"},{"last_name":"Neiner","full_name":"Neiner, C.","first_name":"C."}],"date_created":"2022-07-18T12:10:59Z","article_type":"original","volume":650},{"oa":1,"language":[{"iso":"eng"}],"citation":{"ama":"Mathis S, Bugnet LA, Prat V, Augustson K, Mathur S, Garcia RA. Probing the internal magnetism of stars using asymptotic magneto-asteroseismology. <i>Astronomy &#38; Astrophysics</i>. 2021;647. doi:<a href=\"https://doi.org/10.1051/0004-6361/202039180\">10.1051/0004-6361/202039180</a>","ieee":"S. Mathis, L. A. Bugnet, V. Prat, K. Augustson, S. Mathur, and R. A. Garcia, “Probing the internal magnetism of stars using asymptotic magneto-asteroseismology,” <i>Astronomy &#38; Astrophysics</i>, vol. 647. EDP Sciences, 2021.","short":"S. Mathis, L.A. Bugnet, V. Prat, K. Augustson, S. Mathur, R.A. Garcia, Astronomy &#38; Astrophysics 647 (2021).","chicago":"Mathis, S., Lisa Annabelle Bugnet, V. Prat, K. Augustson, S. Mathur, and R. A. Garcia. “Probing the Internal Magnetism of Stars Using Asymptotic Magneto-Asteroseismology.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2021. <a href=\"https://doi.org/10.1051/0004-6361/202039180\">https://doi.org/10.1051/0004-6361/202039180</a>.","ista":"Mathis S, Bugnet LA, Prat V, Augustson K, Mathur S, Garcia RA. 2021. Probing the internal magnetism of stars using asymptotic magneto-asteroseismology. Astronomy &#38; Astrophysics. 647, A122.","apa":"Mathis, S., Bugnet, L. A., Prat, V., Augustson, K., Mathur, S., &#38; Garcia, R. A. (2021). Probing the internal magnetism of stars using asymptotic magneto-asteroseismology. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202039180\">https://doi.org/10.1051/0004-6361/202039180</a>","mla":"Mathis, S., et al. “Probing the Internal Magnetism of Stars Using Asymptotic Magneto-Asteroseismology.” <i>Astronomy &#38; Astrophysics</i>, vol. 647, A122, EDP Sciences, 2021, doi:<a href=\"https://doi.org/10.1051/0004-6361/202039180\">10.1051/0004-6361/202039180</a>."},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","arxiv":1,"month":"03","article_number":"A122","intvolume":"       647","abstract":[{"text":"Context. Our knowledge of the dynamics of stars has undergone a revolution through the simultaneous large amount of high-quality photometric observations collected by space-based asteroseismology and ground-based high-precision spectropolarimetry. They allowed us to probe the internal rotation of stars and their surface magnetism in the whole Hertzsprung-Russell diagram. However, new methods should still be developed to probe the deep magnetic fields in these stars.\r\n\r\nAims. Our goal is to provide seismic diagnoses that allow us to probe the internal magnetism of stars.\r\n\r\nMethods. We focused on asymptotic low-frequency gravity modes and high-frequency acoustic modes. Using a first-order perturbative theory, we derived magnetic splittings of their frequencies as explicit functions of stellar parameters.\r\n\r\nResults. As in the case of rotation, we show that asymptotic gravity and acoustic modes can allow us to probe the different components of the magnetic field in the cavities in which they propagate. This again demonstrates the high potential of using mixed-modes when this is possible.","lang":"eng"}],"publication_status":"published","publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"day":"18","scopus_import":"1","author":[{"full_name":"Mathis, S.","last_name":"Mathis","first_name":"S."},{"last_name":"Bugnet","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle","orcid":"0000-0003-0142-4000","first_name":"Lisa Annabelle"},{"first_name":"V.","full_name":"Prat, V.","last_name":"Prat"},{"last_name":"Augustson","full_name":"Augustson, K.","first_name":"K."},{"first_name":"S.","last_name":"Mathur","full_name":"Mathur, S."},{"last_name":"Garcia","full_name":"Garcia, R. A.","first_name":"R. A."}],"oa_version":"Preprint","title":"Probing the internal magnetism of stars using asymptotic magneto-asteroseismology","volume":647,"date_created":"2022-07-18T12:15:27Z","article_type":"original","extern":"1","publication":"Astronomy & Astrophysics","status":"public","date_published":"2021-03-18T00:00:00Z","acknowledgement":"The authors thank the referee and Pr. J. Christensen-Dalsgaard for their very constructive comments and remarks that allowed us to improve the article. St. M., L. B., V. P., and K. A. acknowledge support from the European Research Council through ERC grant SPIRE 647383. All the members from CEA acknowledge support from GOLF and PLATO CNES grants of the Astrophysics Division at CEA. S. Mathur acknowledges support by the Ramon y Cajal fellowship number RYC-2015-17697. We made great use of the megyr python package for interfacing MESA and GYRE codes.","year":"2021","external_id":{"arxiv":["2012.11050"]},"keyword":["Space and Planetary Science","Astronomy and Astrophysics","asteroseismology / waves / stars","magnetic field / stars","oscillations / methods","analytical"],"main_file_link":[{"url":"https://arxiv.org/abs/2012.11050","open_access":"1"}],"quality_controlled":"1","article_processing_charge":"No","doi":"10.1051/0004-6361/202039180","publisher":"EDP Sciences","_id":"11606","date_updated":"2022-08-19T10:11:52Z","type":"journal_article"},{"arxiv":1,"month":"03","article_number":"A125","oa":1,"language":[{"iso":"eng"}],"citation":{"ieee":"S. N. Breton, A. R. G. Santos, L. A. Bugnet, S. Mathur, R. A. García, and P. L. Pallé, “ROOSTER: A machine-learning analysis tool for Kepler stellar rotation periods,” <i>Astronomy &#38; Astrophysics</i>, vol. 647. EDP Sciences, 2021.","short":"S.N. Breton, A.R.G. Santos, L.A. Bugnet, S. Mathur, R.A. García, P.L. Pallé, Astronomy &#38; Astrophysics 647 (2021).","ama":"Breton SN, Santos ARG, Bugnet LA, Mathur S, García RA, Pallé PL. ROOSTER: A machine-learning analysis tool for Kepler stellar rotation periods. <i>Astronomy &#38; Astrophysics</i>. 2021;647. doi:<a href=\"https://doi.org/10.1051/0004-6361/202039947\">10.1051/0004-6361/202039947</a>","apa":"Breton, S. N., Santos, A. R. G., Bugnet, L. A., Mathur, S., García, R. A., &#38; Pallé, P. L. (2021). ROOSTER: A machine-learning analysis tool for Kepler stellar rotation periods. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202039947\">https://doi.org/10.1051/0004-6361/202039947</a>","mla":"Breton, S. N., et al. “ROOSTER: A Machine-Learning Analysis Tool for Kepler Stellar Rotation Periods.” <i>Astronomy &#38; Astrophysics</i>, vol. 647, A125, EDP Sciences, 2021, doi:<a href=\"https://doi.org/10.1051/0004-6361/202039947\">10.1051/0004-6361/202039947</a>.","chicago":"Breton, S. N., A. R. G. Santos, Lisa Annabelle Bugnet, S. Mathur, R. A. García, and P. L. Pallé. “ROOSTER: A Machine-Learning Analysis Tool for Kepler Stellar Rotation Periods.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2021. <a href=\"https://doi.org/10.1051/0004-6361/202039947\">https://doi.org/10.1051/0004-6361/202039947</a>.","ista":"Breton SN, Santos ARG, Bugnet LA, Mathur S, García RA, Pallé PL. 2021. ROOSTER: A machine-learning analysis tool for Kepler stellar rotation periods. Astronomy &#38; Astrophysics. 647, A125."},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","scopus_import":"1","day":"19","author":[{"full_name":"Breton, S. N.","last_name":"Breton","first_name":"S. N."},{"full_name":"Santos, A. R. G.","last_name":"Santos","first_name":"A. R. G."},{"orcid":"0000-0003-0142-4000","first_name":"Lisa Annabelle","last_name":"Bugnet","full_name":"Bugnet, Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501"},{"last_name":"Mathur","full_name":"Mathur, S.","first_name":"S."},{"first_name":"R. A.","full_name":"García, R. A.","last_name":"García"},{"full_name":"Pallé, P. L.","last_name":"Pallé","first_name":"P. L."}],"title":"ROOSTER: A machine-learning analysis tool for Kepler stellar rotation periods","oa_version":"Preprint","volume":647,"date_created":"2022-07-18T12:21:32Z","article_type":"original","abstract":[{"text":"In order to understand stellar evolution, it is crucial to efficiently determine stellar surface rotation periods. Indeed, while they are of great importance in stellar models, angular momentum transport processes inside stars are still poorly understood today. Surface rotation, which is linked to the age of the star, is one of the constraints needed to improve the way those processes are modelled. Statistics of the surface rotation periods for a large sample of stars of different spectral types are thus necessary. An efficient tool to automatically determine reliable rotation periods is needed when dealing with large samples of stellar photometric datasets. The objective of this work is to develop such a tool. For this purpose, machine learning classifiers constitute relevant bases to build our new methodology. Random forest learning abilities are exploited to automate the extraction of rotation periods in Kepler light curves. Rotation periods and complementary parameters are obtained via three different methods: a wavelet analysis, the autocorrelation function of the light curve, and the composite spectrum. We trained three different classifiers: one to detect if rotational modulations are present in the light curve, one to flag close binary or classical pulsators candidates that can bias our rotation period determination, and finally one classifier to provide the final rotation period. We tested our machine learning pipeline on 23 431 stars of the Kepler K and M dwarf reference rotation catalogue for which 60% of the stars have been visually inspected. For the sample of 21 707 stars where all the input parameters are provided to the algorithm, 94.2% of them are correctly classified (as rotating or not). Among the stars that have a rotation period in the reference catalogue, the machine learning provides a period that agrees within 10% of the reference value for 95.3% of the stars. Moreover, the yield of correct rotation periods is raised to 99.5% after visually inspecting 25.2% of the stars. Over the two main analysis steps, rotation classification and period selection, the pipeline yields a global agreement with the reference values of 92.1% and 96.9% before and after visual inspection. Random forest classifiers are efficient tools to determine reliable rotation periods in large samples of stars. The methodology presented here could be easily adapted to extract surface rotation periods for stars with different spectral types or observed by other instruments such as K2, TESS or by PLATO in the near future.","lang":"eng"}],"intvolume":"       647","publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"publication_status":"published","year":"2021","external_id":{"arxiv":["2101.10152"]},"keyword":["Space and Planetary Science","Astronomy and Astrophysics","methods: data analysis / stars: solar-type / stars: activity / stars: rotation / starspots"],"extern":"1","status":"public","publication":"Astronomy & Astrophysics","date_published":"2021-03-19T00:00:00Z","acknowledgement":"We thank Suzanne Aigrain and Joe Llama for providing us with the simulated data used in Aigrain et al. (2015). S. N. B., L. B. and R. A. G. acknowledge the support from PLATO and GOLF CNES grants. A. R. G. S. acknowledges the support from NASA under grant NNX17AF27G. S. M. acknowledges the support from the Spanish Ministry of Science and Innovation with the Ramon y Cajal fellowship number RYC-2015-17697. P. L. P. and S. M. acknowledge support from the Spanish Ministry of Science and Innovation with the grant number PID2019-107187GB-I00. This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Software: Python (Van Rossum & Drake 2009), numpy (Oliphant 2006), pandas (The pandas development team 2020; McKinney 2010), matplotlib (Hunter 2007), scikit-learn (Pedregosa et al. 2011). The source code used to obtain the present results can be found at: https://gitlab.com/sybreton/pushkin ; https://gitlab.com/sybreton/ml_surface_rotation_paper .","article_processing_charge":"No","doi":"10.1051/0004-6361/202039947","publisher":"EDP Sciences","_id":"11608","date_updated":"2022-08-22T08:47:47Z","type":"journal_article","main_file_link":[{"url":"https://arxiv.org/abs/2101.10152","open_access":"1"}],"quality_controlled":"1"},{"month":"02","arxiv":1,"article_number":"A64","language":[{"iso":"eng"}],"oa":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","citation":{"ieee":"J. Park, V. Prat, S. Mathis, and L. A. Bugnet, “Horizontal shear instabilities in rotating stellar radiation zones: II. Effects of the full Coriolis acceleration,” <i>Astronomy &#38; Astrophysics</i>, vol. 646. EDP Sciences, 2021.","short":"J. Park, V. Prat, S. Mathis, L.A. Bugnet, Astronomy &#38; Astrophysics 646 (2021).","ama":"Park J, Prat V, Mathis S, Bugnet LA. Horizontal shear instabilities in rotating stellar radiation zones: II. Effects of the full Coriolis acceleration. <i>Astronomy &#38; Astrophysics</i>. 2021;646. doi:<a href=\"https://doi.org/10.1051/0004-6361/202038654\">10.1051/0004-6361/202038654</a>","apa":"Park, J., Prat, V., Mathis, S., &#38; Bugnet, L. A. (2021). Horizontal shear instabilities in rotating stellar radiation zones: II. Effects of the full Coriolis acceleration. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202038654\">https://doi.org/10.1051/0004-6361/202038654</a>","mla":"Park, J., et al. “Horizontal Shear Instabilities in Rotating Stellar Radiation Zones: II. Effects of the Full Coriolis Acceleration.” <i>Astronomy &#38; Astrophysics</i>, vol. 646, A64, EDP Sciences, 2021, doi:<a href=\"https://doi.org/10.1051/0004-6361/202038654\">10.1051/0004-6361/202038654</a>.","ista":"Park J, Prat V, Mathis S, Bugnet LA. 2021. Horizontal shear instabilities in rotating stellar radiation zones: II. Effects of the full Coriolis acceleration. Astronomy &#38; Astrophysics. 646, A64.","chicago":"Park, J., V. Prat, S. Mathis, and Lisa Annabelle Bugnet. “Horizontal Shear Instabilities in Rotating Stellar Radiation Zones: II. Effects of the Full Coriolis Acceleration.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2021. <a href=\"https://doi.org/10.1051/0004-6361/202038654\">https://doi.org/10.1051/0004-6361/202038654</a>."},"title":"Horizontal shear instabilities in rotating stellar radiation zones: II. Effects of the full Coriolis acceleration","oa_version":"Preprint","scopus_import":"1","day":"08","author":[{"last_name":"Park","full_name":"Park, J.","first_name":"J."},{"last_name":"Prat","full_name":"Prat, V.","first_name":"V."},{"last_name":"Mathis","full_name":"Mathis, S.","first_name":"S."},{"full_name":"Bugnet, Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501","last_name":"Bugnet","first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000"}],"date_created":"2022-07-18T13:24:32Z","article_type":"original","volume":646,"abstract":[{"lang":"eng","text":"Context. Stellar interiors are the seat of efficient transport of angular momentum all along their evolution. In this context, understanding the dependence of the turbulent transport triggered by the instabilities of the vertical and horizontal shears of the differential rotation in stellar radiation zones as a function of their rotation, stratification, and thermal diffusivity is mandatory. Indeed, it constitutes one of the cornerstones of the rotational transport and mixing theory, which is implemented in stellar evolution codes to predict the rotational and chemical evolutions of stars.\r\n\r\nAims. We investigate horizontal shear instabilities in rotating stellar radiation zones by considering the full Coriolis acceleration with both the dimensionless horizontal Coriolis component f̃ and the vertical component f.\r\n\r\nMethods. We performed a linear stability analysis using linearized equations derived from the Navier-Stokes and heat transport equations in the rotating nontraditional f-plane. We considered a horizontal shear flow with a hyperbolic tangent profile as the base flow. The linear stability was analyzed numerically in wide ranges of parameters, and we performed an asymptotic analysis for large vertical wavenumbers using the Wentzel-Kramers-Brillouin-Jeffreys (WKBJ) approximation for nondiffusive and highly-diffusive fluids.\r\n\r\nResults. As in the traditional f-plane approximation, we identify two types of instabilities: the inflectional and inertial instabilities. The inflectional instability is destabilized as f̃ increases and its maximum growth rate increases significantly, while the thermal diffusivity stabilizes the inflectional instability similarly to the traditional case. The inertial instability is also strongly affected; for instance, the inertially unstable regime is also extended in the nondiffusive limit as 0 < f < 1 + f̃ 2/N2, where N is the dimensionless Brunt-Väisälä frequency. More strikingly, in the high thermal diffusivity limit, it is always inertially unstable at any colatitude θ except at the poles (i.e., 0° < θ <  180°). We also derived the critical Reynolds numbers for the inertial instability using the asymptotic dispersion relations obtained from the WKBJ analysis. Using the asymptotic and numerical results, we propose a prescription for the effective turbulent viscosities induced by the inertial and inflectional instabilities that can be possibly used in stellar evolution models. The characteristic time of this turbulence is short enough so that it is efficient to redistribute angular momentum and to mix chemicals in stellar radiation zones."}],"intvolume":"       646","publication_identifier":{"issn":["0004-6361"],"eissn":["1432-0746"]},"publication_status":"published","external_id":{"arxiv":["2006.10660"]},"year":"2021","keyword":["Space and Planetary Science","Astronomy and Astrophysics","hydrodynamics / turbulence / stars","rotation / stars","evolution"],"status":"public","publication":"Astronomy & Astrophysics","extern":"1","date_published":"2021-02-08T00:00:00Z","acknowledgement":"The authors acknowledge support from the European Research Council through ERC grant SPIRE 647383 and from GOLF and PLATO CNES grants at the Department of Astrophysics at CEA Paris-Saclay. We thank the referee, Prof. A. J. Barker, for his constructive comments that allow us to improve the article.","publisher":"EDP Sciences","article_processing_charge":"No","doi":"10.1051/0004-6361/202038654","type":"journal_article","_id":"11609","date_updated":"2022-08-19T10:18:03Z","quality_controlled":"1","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2006.10660"}]},{"quality_controlled":"1","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2012.04051"}],"type":"journal_article","date_updated":"2022-08-22T07:04:45Z","_id":"11610","publisher":"IOP Publishing","doi":"10.3847/1538-4365/abbee3","article_processing_charge":"No","date_published":"2020-12-01T00:00:00Z","acknowledgement":"We thank the referee for comments that strengthened the manuscript. J. C. Z. and M. H. P. acknowledge support from NASA grants 80NSSC18K0391 and NNX17AJ40G. Y. E. and C. J. acknowledge the support of the UK Science and Technology Facilities Council (STFC). S. M. would like to acknowledge support from the Spanish Ministry with the Ramon y Cajal fellowship number RYC-2015-17697. R. A. G. acknowledges funding received from the PLATO CNES grant. R. S. acknowledges funding via a Royal Society University Research Fellowship. D.H. acknowledges support from the Alfred P. Sloan Foundation and the National Aeronautics and Space Administration (80NSSC19K0108). V.S.A. acknowledges support from the Independent Research Fund Denmark (Research grant 7027-00096B), and the Carlsberg foundation (grant agreement CF19-0649). This research was supported in part by the National Science Foundation under grant No. NSF PHY-1748958.\r\n\r\nFunding for the Stellar Astrophysics Centre (SAC) is provided by The Danish National Research Foundation (grant agreement No. DNRF106).\r\n\r\nThe K2 Galactic Archaeology Program is supported by the National Aeronautics and Space Administration under grant NNX16AJ17G issued through the K2 Guest Observer Program.\r\n\r\nThis publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation.\r\n\r\nThis work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.\r\n\r\nFunding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS-IV acknowledges support and resources from the Center for High Performance Computing at the University of Utah. The SDSS website is www.sdss.org.\r\n\r\nSDSS-IV is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS Collaboration, including the Brazilian Participation Group, the Carnegie Institution for Science, Carnegie Mellon University, the Chilean Participation Group, the French Participation Group, the Harvard–Smithsonian Center for Astrophysics, Instituto de Astrofísica de Canarias, The Johns Hopkins University, Kavli Institute for the Physics and Mathematics of the Universe (IPMU)/University of Tokyo, the Korean Participation Group, Lawrence Berkeley National Laboratory, Leibniz Institut für Astrophysik Potsdam (AIP), Max-Planck-Institut für Astronomie (MPIA Heidelberg), Max-Planck-Institut für Astrophysik (MPA Garching), Max-Planck-Institut für Extraterrestrische Physik (MPE), National Astronomical Observatories of China, New Mexico State University, New York University, University of Notre Dame, Observatário Nacional/MCTI, The Ohio State University, Pennsylvania State University, Shanghai Astronomical Observatory, United Kingdom Participation Group, Universidad Nacional Autónoma de México, University of Arizona, University of Colorado Boulder, University of Oxford, University of Portsmouth, University of Utah, University of Virginia, University of Washington, University of Wisconsin, Vanderbilt University, and Yale University.\r\n\r\nSoftware: asfgrid (Sharma & Stello 2016), emcee (Foreman-Mackey et al. 2013), NumPy (Walt 2011), pandas (McKinney 2010; Reback et al. 2020), Matplotlib (Hunter 2007), IPython (Pérez & Granger 2007), SciPy (Virtanen et al. 2020).","status":"public","extern":"1","publication":"The Astrophysical Journal Supplement Series","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"external_id":{"arxiv":["2012.04051"]},"year":"2020","publication_status":"published","publication_identifier":{"eissn":["1538-4365"],"issn":["0067-0049"]},"intvolume":"       251","abstract":[{"text":"Studies of Galactic structure and evolution have benefited enormously from Gaia kinematic information, though additional, intrinsic stellar parameters like age are required to best constrain Galactic models. Asteroseismology is the most precise method of providing such information for field star populations en masse, but existing samples for the most part have been limited to a few narrow fields of view by the CoRoT and Kepler missions. In an effort to provide well-characterized stellar parameters across a wide range in Galactic position, we present the second data release of red giant asteroseismic parameters for the K2 Galactic Archaeology Program (GAP). We provide ${\\nu }_{\\max }$ and ${\\rm{\\Delta }}\\nu $ based on six independent pipeline analyses; first-ascent red giant branch (RGB) and red clump (RC) evolutionary state classifications from machine learning; and ready-to-use radius and mass coefficients, κR and κM, which, when appropriately multiplied by a solar-scaled effective temperature factor, yield physical stellar radii and masses. In total, we report 4395 radius and mass coefficients, with typical uncertainties of 3.3% (stat.) ± 1% (syst.) for κR and 7.7% (stat.) ± 2% (syst.) for κM among RGB stars, and 5.0% (stat.) ± 1% (syst.) for κR and 10.5% (stat.) ± 2% (syst.) for κM among RC stars. We verify that the sample is nearly complete—except for a dearth of stars with ${\\nu }_{\\max }\\lesssim 10\\mbox{--}20\\,\\mu \\mathrm{Hz}$—by comparing to Galactic models and visual inspection. Our asteroseismic radii agree with radii derived from Gaia Data Release 2 parallaxes to within 2.2% ± 0.3% for RGB stars and 2.0% ± 0.6% for RC stars.","lang":"eng"}],"article_type":"original","date_created":"2022-07-18T13:27:26Z","volume":251,"title":"The K2 galactic archaeology program data release 2: Asteroseismic results from campaigns 4, 6, and 7","oa_version":"Preprint","author":[{"full_name":"Zinn, Joel C.","last_name":"Zinn","first_name":"Joel C."},{"full_name":"Stello, Dennis","last_name":"Stello","first_name":"Dennis"},{"first_name":"Yvonne","full_name":"Elsworth, Yvonne","last_name":"Elsworth"},{"first_name":"Rafael A.","full_name":"García, Rafael A.","last_name":"García"},{"first_name":"Thomas","full_name":"Kallinger, Thomas","last_name":"Kallinger"},{"first_name":"Savita","full_name":"Mathur, Savita","last_name":"Mathur"},{"full_name":"Mosser, Benoît","last_name":"Mosser","first_name":"Benoît"},{"orcid":"0000-0003-0142-4000","first_name":"Lisa Annabelle","full_name":"Bugnet, Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501","last_name":"Bugnet"},{"first_name":"Caitlin","full_name":"Jones, Caitlin","last_name":"Jones"},{"first_name":"Marc","full_name":"Hon, Marc","last_name":"Hon"},{"last_name":"Sharma","full_name":"Sharma, Sanjib","first_name":"Sanjib"},{"last_name":"Schönrich","full_name":"Schönrich, Ralph","first_name":"Ralph"},{"first_name":"Jack T.","full_name":"Warfield, Jack T.","last_name":"Warfield"},{"first_name":"Rodrigo","last_name":"Luger","full_name":"Luger, Rodrigo"},{"first_name":"Marc H.","last_name":"Pinsonneault","full_name":"Pinsonneault, Marc H."},{"full_name":"Johnson, Jennifer A.","last_name":"Johnson","first_name":"Jennifer A."},{"full_name":"Huber, Daniel","last_name":"Huber","first_name":"Daniel"},{"first_name":"Victor Silva","last_name":"Aguirre","full_name":"Aguirre, Victor Silva"},{"full_name":"Chaplin, William J.","last_name":"Chaplin","first_name":"William J."},{"last_name":"Davies","full_name":"Davies, Guy R.","first_name":"Guy R."},{"first_name":"Andrea","full_name":"Miglio, Andrea","last_name":"Miglio"}],"scopus_import":"1","day":"01","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","issue":"2","citation":{"chicago":"Zinn, Joel C., Dennis Stello, Yvonne Elsworth, Rafael A. García, Thomas Kallinger, Savita Mathur, Benoît Mosser, et al. “The K2 Galactic Archaeology Program Data Release 2: Asteroseismic Results from Campaigns 4, 6, and 7.” <i>The Astrophysical Journal Supplement Series</i>. IOP Publishing, 2020. <a href=\"https://doi.org/10.3847/1538-4365/abbee3\">https://doi.org/10.3847/1538-4365/abbee3</a>.","ista":"Zinn JC, Stello D, Elsworth Y, García RA, Kallinger T, Mathur S, Mosser B, Bugnet LA, Jones C, Hon M, Sharma S, Schönrich R, Warfield JT, Luger R, Pinsonneault MH, Johnson JA, Huber D, Aguirre VS, Chaplin WJ, Davies GR, Miglio A. 2020. The K2 galactic archaeology program data release 2: Asteroseismic results from campaigns 4, 6, and 7. The Astrophysical Journal Supplement Series. 251(2), 23.","mla":"Zinn, Joel C., et al. “The K2 Galactic Archaeology Program Data Release 2: Asteroseismic Results from Campaigns 4, 6, and 7.” <i>The Astrophysical Journal Supplement Series</i>, vol. 251, no. 2, 23, IOP Publishing, 2020, doi:<a href=\"https://doi.org/10.3847/1538-4365/abbee3\">10.3847/1538-4365/abbee3</a>.","apa":"Zinn, J. C., Stello, D., Elsworth, Y., García, R. A., Kallinger, T., Mathur, S., … Miglio, A. (2020). The K2 galactic archaeology program data release 2: Asteroseismic results from campaigns 4, 6, and 7. <i>The Astrophysical Journal Supplement Series</i>. IOP Publishing. <a href=\"https://doi.org/10.3847/1538-4365/abbee3\">https://doi.org/10.3847/1538-4365/abbee3</a>","ama":"Zinn JC, Stello D, Elsworth Y, et al. The K2 galactic archaeology program data release 2: Asteroseismic results from campaigns 4, 6, and 7. <i>The Astrophysical Journal Supplement Series</i>. 2020;251(2). doi:<a href=\"https://doi.org/10.3847/1538-4365/abbee3\">10.3847/1538-4365/abbee3</a>","short":"J.C. Zinn, D. Stello, Y. Elsworth, R.A. García, T. Kallinger, S. Mathur, B. Mosser, L.A. Bugnet, C. Jones, M. Hon, S. Sharma, R. Schönrich, J.T. Warfield, R. Luger, M.H. Pinsonneault, J.A. Johnson, D. Huber, V.S. Aguirre, W.J. Chaplin, G.R. Davies, A. Miglio, The Astrophysical Journal Supplement Series 251 (2020).","ieee":"J. C. Zinn <i>et al.</i>, “The K2 galactic archaeology program data release 2: Asteroseismic results from campaigns 4, 6, and 7,” <i>The Astrophysical Journal Supplement Series</i>, vol. 251, no. 2. IOP Publishing, 2020."},"language":[{"iso":"eng"}],"oa":1,"article_number":"23","month":"12","arxiv":1},{"page":"382-389","quality_controlled":"1","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2001.04653"}],"publisher":"Springer Nature","doi":"10.1038/s41550-019-0975-9","article_processing_charge":"No","type":"journal_article","date_updated":"2022-08-22T07:08:29Z","_id":"11611","status":"public","publication":"Nature Astronomy","extern":"1","acknowledgement":"This paper includes data collected by the TESS mission, which are publicly available from the Mikulski Archive for Space Telescopes (MAST). Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. W.J.C. acknowledges support from the UK Science and Technology Facilities Council (STFC) and UK Space Agency. Funding for the Stellar Astrophysics Centre is provided by The Danish National Research Foundation (grant agreement number DNRF106). This research was partially conducted during the Exostar19 programme at the Kavli Institute for Theoretical Physics at UC Santa Barbara, which was supported in part by the National Science Foundation under grant number NSF PHY-1748958. A.M., J.T.M., F.V. and J.M. acknowledge support from the ERC Consolidator Grant funding scheme (project ASTEROCHRONOMETRY, grant agreement number 772293). F.V. acknowledges the support of a Fellowship from the Center for Cosmology and AstroParticle Physics at The Ohio State University. W.H.B. and M.B.N. acknowledge support from the UK Space Agency. K.J.B. is supported by the National Science Foundation under award AST-1903828. M.B.N. acknowledges partial support from the NYU Abu Dhabi Center for Space Science under grant number G1502. A.M.S. is partially supported by the Spanish Government (ESP2017-82674-R) and Generalitat de Catalunya (2017-SGR-1131). T.M. acknowledges financial support from Belspo for contract PRODEX PLATO. H.K. acknowledges support from the European Social Fund via the Lithuanian Science Council grant number 09.3.3-LMT-K-712-01-0103. S.B. acknowledges support from NSF grant AST-1514676 and NASA grant 80NSSC19K0374. V.S.A. acknowledges support from the Independent Research Fund Denmark (research grant 7027-00096B). D.H. acknowledges support by the National Aeronautics and Space Administration (80NSSC18K1585, 80NSSC19K0379) awarded through the TESS Guest Investigator Program and by the National Science Foundation (AST-1717000). T.S.M. acknowledges support from a visiting fellowship at the Max Planck Institute for Solar System Research. Computational resources were provided through XSEDE allocation TG-AST090107. D.L.B. acknowledges support from NASA under grant NNX16AB76G. T.L.C. acknowledges support from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement number 792848 (PULSATION). This work was supported by FCT/MCTES through national funds (PIDDAC) by means of grant UID/FIS/04434/2019. K.J.B., S.H., J.S.K. and N.T. are supported by the European Research Council under the European Community’s Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement number 338251 (StellarAges). E.C. is funded by the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement number 664931. L.G.-C. acknowledges support from the MINECO FPI-SO doctoral research project SEV-2015-0548-17-2 and predoctoral contract BES-2017-082610. P.G. is supported by the German space agency (Deutsches Zentrum für Luft- und Raumfahrt) under PLATO data grant 50OO1501. R.K. acknowledges support from the UK Science and Technology Facilities Council (STFC), under consolidated grant ST/L000733/1. M.S.L. is supported by the Carlsberg Foundation (grant agreement number CF17-076). Z.C.O., S.O. and M.Y. acknowledge support from the Scientific and Technological Research Council of Turkey (TÜBİTAK:118F352). S.M. acknowledges support from the Spanish ministry through the Ramon y Cajal fellowship number RYC-2015-17697. T.S.R. acknowledges financial support from Premiale 2015 MITiC (PI B. Garilli). R.Sz. acknowledges the support from NKFIH grant project No. K-115709, and the Lendület program of the Hungarian Academy of Science (project number 2018-7/2019). J.T. acknowledges support was provided by NASA through the NASA Hubble Fellowship grant number 51424 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. This work was supported by FEDER through COMPETE2020 (POCI-01-0145-FEDER-030389. A.M.B. acknowledges funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 749962 (project THOT). A.M. and P.R. acknowledge the support of the Government of India, Department of Atomic Energy, under Project No. 12-R&D-TFR-6.04-0600. K.J.B. is an NSF Astronomy and Astrophysics Postdoctoral Fellow and DIRAC Fellow.","date_published":"2020-04-01T00:00:00Z","external_id":{"arxiv":["2001.04653"]},"year":"2020","keyword":["Astronomy and Astrophysics"],"intvolume":"         4","abstract":[{"text":"Over the course of its history, the Milky Way has ingested multiple smaller satellite galaxies1. Although these accreted stellar populations can be forensically identified as kinematically distinct structures within the Galaxy, it is difficult in general to date precisely the age at which any one merger occurred. Recent results have revealed a population of stars that were accreted via the collision of a dwarf galaxy, called Gaia–Enceladus1, leading to substantial pollution of the chemical and dynamical properties of the Milky Way. Here we identify the very bright, naked-eye star ν Indi as an indicator of the age of the early in situ population of the Galaxy. We combine asteroseismic, spectroscopic, astrometric and kinematic observations to show that this metal-poor, alpha-element-rich star was an indigenous member of the halo, and we measure its age to be 11.0±0.7 (stat) ±0.8 (sys) billion years. The star bears hallmarks consistent with having been kinematically heated by the Gaia–Enceladus collision. Its age implies that the earliest the merger could have begun was 11.6 and 13.2 billion years ago, at 68% and 95% confidence, respectively. Computations based on hierarchical cosmological models slightly reduce the above limits.","lang":"eng"}],"publication_status":"published","publication_identifier":{"eissn":["2397-3366"]},"title":"Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi","oa_version":"Preprint","author":[{"first_name":"William J.","full_name":"Chaplin, William J.","last_name":"Chaplin"},{"full_name":"Serenelli, Aldo M.","last_name":"Serenelli","first_name":"Aldo M."},{"first_name":"Andrea","full_name":"Miglio, Andrea","last_name":"Miglio"},{"full_name":"Morel, Thierry","last_name":"Morel","first_name":"Thierry"},{"first_name":"J. Ted","full_name":"Mackereth, J. Ted","last_name":"Mackereth"},{"first_name":"Fiorenzo","full_name":"Vincenzo, Fiorenzo","last_name":"Vincenzo"},{"last_name":"Kjeldsen","full_name":"Kjeldsen, Hans","first_name":"Hans"},{"first_name":"Sarbani","last_name":"Basu","full_name":"Basu, Sarbani"},{"first_name":"Warrick H.","full_name":"Ball, Warrick H.","last_name":"Ball"},{"last_name":"Stokholm","full_name":"Stokholm, Amalie","first_name":"Amalie"},{"last_name":"Verma","full_name":"Verma, Kuldeep","first_name":"Kuldeep"},{"last_name":"Mosumgaard","full_name":"Mosumgaard, Jakob Rørsted","first_name":"Jakob Rørsted"},{"first_name":"Victor","full_name":"Silva Aguirre, Victor","last_name":"Silva Aguirre"},{"full_name":"Mazumdar, Anwesh","last_name":"Mazumdar","first_name":"Anwesh"},{"first_name":"Pritesh","last_name":"Ranadive","full_name":"Ranadive, Pritesh"},{"first_name":"H. M.","full_name":"Antia, H. M.","last_name":"Antia"},{"first_name":"Yveline","full_name":"Lebreton, Yveline","last_name":"Lebreton"},{"last_name":"Ong","full_name":"Ong, Joel","first_name":"Joel"},{"last_name":"Appourchaux","full_name":"Appourchaux, Thierry","first_name":"Thierry"},{"last_name":"Bedding","full_name":"Bedding, Timothy R.","first_name":"Timothy R."},{"first_name":"Jørgen","full_name":"Christensen-Dalsgaard, Jørgen","last_name":"Christensen-Dalsgaard"},{"first_name":"Orlagh","full_name":"Creevey, Orlagh","last_name":"Creevey"},{"first_name":"Rafael A.","full_name":"García, Rafael A.","last_name":"García"},{"last_name":"Handberg","full_name":"Handberg, Rasmus","first_name":"Rasmus"},{"first_name":"Daniel","last_name":"Huber","full_name":"Huber, Daniel"},{"first_name":"Steven D.","full_name":"Kawaler, Steven D.","last_name":"Kawaler"},{"full_name":"Lund, Mikkel N.","last_name":"Lund","first_name":"Mikkel N."},{"first_name":"Travis S.","last_name":"Metcalfe","full_name":"Metcalfe, Travis S."},{"first_name":"Keivan G.","last_name":"Stassun","full_name":"Stassun, Keivan G."},{"last_name":"Bazot","full_name":"Bazot, Michäel","first_name":"Michäel"},{"full_name":"Beck, Paul G.","last_name":"Beck","first_name":"Paul G."},{"last_name":"Bell","full_name":"Bell, Keaton J.","first_name":"Keaton J."},{"first_name":"Maria","full_name":"Bergemann, Maria","last_name":"Bergemann"},{"full_name":"Buzasi, Derek L.","last_name":"Buzasi","first_name":"Derek L."},{"last_name":"Benomar","full_name":"Benomar, Othman","first_name":"Othman"},{"first_name":"Diego","full_name":"Bossini, Diego","last_name":"Bossini"},{"last_name":"Bugnet","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle","orcid":"0000-0003-0142-4000","first_name":"Lisa Annabelle"},{"first_name":"Tiago L.","full_name":"Campante, Tiago L.","last_name":"Campante"},{"first_name":"Zeynep Çelik","full_name":"Orhan, Zeynep Çelik","last_name":"Orhan"},{"first_name":"Enrico","full_name":"Corsaro, Enrico","last_name":"Corsaro"},{"first_name":"Lucía","full_name":"González-Cuesta, Lucía","last_name":"González-Cuesta"},{"last_name":"Davies","full_name":"Davies, Guy R.","first_name":"Guy R."},{"full_name":"Di Mauro, Maria Pia","last_name":"Di Mauro","first_name":"Maria Pia"},{"last_name":"Egeland","full_name":"Egeland, Ricky","first_name":"Ricky"},{"last_name":"Elsworth","full_name":"Elsworth, Yvonne P.","first_name":"Yvonne P."},{"first_name":"Patrick","last_name":"Gaulme","full_name":"Gaulme, Patrick"},{"first_name":"Hamed","last_name":"Ghasemi","full_name":"Ghasemi, Hamed"},{"full_name":"Guo, Zhao","last_name":"Guo","first_name":"Zhao"},{"first_name":"Oliver J.","full_name":"Hall, Oliver J.","last_name":"Hall"},{"last_name":"Hasanzadeh","full_name":"Hasanzadeh, Amir","first_name":"Amir"},{"full_name":"Hekker, Saskia","last_name":"Hekker","first_name":"Saskia"},{"first_name":"Rachel","full_name":"Howe, Rachel","last_name":"Howe"},{"first_name":"Jon M.","full_name":"Jenkins, Jon M.","last_name":"Jenkins"},{"last_name":"Jiménez","full_name":"Jiménez, Antonio","first_name":"Antonio"},{"full_name":"Kiefer, René","last_name":"Kiefer","first_name":"René"},{"last_name":"Kuszlewicz","full_name":"Kuszlewicz, James S.","first_name":"James S."},{"full_name":"Kallinger, Thomas","last_name":"Kallinger","first_name":"Thomas"},{"first_name":"David W.","last_name":"Latham","full_name":"Latham, David W."},{"full_name":"Lundkvist, Mia S.","last_name":"Lundkvist","first_name":"Mia S."},{"full_name":"Mathur, Savita","last_name":"Mathur","first_name":"Savita"},{"full_name":"Montalbán, Josefina","last_name":"Montalbán","first_name":"Josefina"},{"first_name":"Benoit","last_name":"Mosser","full_name":"Mosser, Benoit"},{"first_name":"Andres Moya","full_name":"Bedón, Andres Moya","last_name":"Bedón"},{"full_name":"Nielsen, Martin Bo","last_name":"Nielsen","first_name":"Martin Bo"},{"first_name":"Sibel","last_name":"Örtel","full_name":"Örtel, Sibel"},{"full_name":"Rendle, Ben M.","last_name":"Rendle","first_name":"Ben M."},{"last_name":"Ricker","full_name":"Ricker, George R.","first_name":"George R."},{"first_name":"Thaíse S.","full_name":"Rodrigues, Thaíse S.","last_name":"Rodrigues"},{"first_name":"Ian W.","last_name":"Roxburgh","full_name":"Roxburgh, Ian W."},{"first_name":"Hossein","last_name":"Safari","full_name":"Safari, Hossein"},{"full_name":"Schofield, Mathew","last_name":"Schofield","first_name":"Mathew"},{"full_name":"Seager, Sara","last_name":"Seager","first_name":"Sara"},{"full_name":"Smalley, Barry","last_name":"Smalley","first_name":"Barry"},{"first_name":"Dennis","last_name":"Stello","full_name":"Stello, Dennis"},{"first_name":"Róbert","full_name":"Szabó, Róbert","last_name":"Szabó"},{"first_name":"Jamie","full_name":"Tayar, Jamie","last_name":"Tayar"},{"full_name":"Themeßl, Nathalie","last_name":"Themeßl","first_name":"Nathalie"},{"full_name":"Thomas, Alexandra E. L.","last_name":"Thomas","first_name":"Alexandra E. L."},{"first_name":"Roland K.","last_name":"Vanderspek","full_name":"Vanderspek, Roland K."},{"first_name":"Walter E.","last_name":"van Rossem","full_name":"van Rossem, Walter E."},{"full_name":"Vrard, Mathieu","last_name":"Vrard","first_name":"Mathieu"},{"first_name":"Achim","full_name":"Weiss, Achim","last_name":"Weiss"},{"first_name":"Timothy R.","last_name":"White","full_name":"White, Timothy R."},{"full_name":"Winn, Joshua N.","last_name":"Winn","first_name":"Joshua N."},{"full_name":"Yıldız, Mutlu","last_name":"Yıldız","first_name":"Mutlu"}],"scopus_import":"1","day":"01","article_type":"letter_note","date_created":"2022-07-18T13:36:19Z","volume":4,"language":[{"iso":"eng"}],"oa":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","issue":"4","citation":{"ama":"Chaplin WJ, Serenelli AM, Miglio A, et al. Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi. <i>Nature Astronomy</i>. 2020;4(4):382-389. doi:<a href=\"https://doi.org/10.1038/s41550-019-0975-9\">10.1038/s41550-019-0975-9</a>","ieee":"W. J. Chaplin <i>et al.</i>, “Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi,” <i>Nature Astronomy</i>, vol. 4, no. 4. Springer Nature, pp. 382–389, 2020.","short":"W.J. Chaplin, A.M. Serenelli, A. Miglio, T. Morel, J.T. Mackereth, F. Vincenzo, H. Kjeldsen, S. Basu, W.H. Ball, A. Stokholm, K. Verma, J.R. Mosumgaard, V. Silva Aguirre, A. Mazumdar, P. Ranadive, H.M. Antia, Y. Lebreton, J. Ong, T. Appourchaux, T.R. Bedding, J. Christensen-Dalsgaard, O. Creevey, R.A. García, R. Handberg, D. Huber, S.D. Kawaler, M.N. Lund, T.S. Metcalfe, K.G. Stassun, M. Bazot, P.G. Beck, K.J. Bell, M. Bergemann, D.L. Buzasi, O. Benomar, D. Bossini, L.A. Bugnet, T.L. Campante, Z.Ç. Orhan, E. Corsaro, L. González-Cuesta, G.R. Davies, M.P. Di Mauro, R. Egeland, Y.P. Elsworth, P. Gaulme, H. Ghasemi, Z. Guo, O.J. Hall, A. Hasanzadeh, S. Hekker, R. Howe, J.M. Jenkins, A. Jiménez, R. Kiefer, J.S. Kuszlewicz, T. Kallinger, D.W. Latham, M.S. Lundkvist, S. Mathur, J. Montalbán, B. Mosser, A.M. Bedón, M.B. Nielsen, S. Örtel, B.M. Rendle, G.R. Ricker, T.S. Rodrigues, I.W. Roxburgh, H. Safari, M. Schofield, S. Seager, B. Smalley, D. Stello, R. Szabó, J. Tayar, N. Themeßl, A.E.L. Thomas, R.K. Vanderspek, W.E. van Rossem, M. Vrard, A. Weiss, T.R. White, J.N. Winn, M. Yıldız, Nature Astronomy 4 (2020) 382–389.","ista":"Chaplin WJ, Serenelli AM, Miglio A, Morel T, Mackereth JT, Vincenzo F, Kjeldsen H, Basu S, Ball WH, Stokholm A, Verma K, Mosumgaard JR, Silva Aguirre V, Mazumdar A, Ranadive P, Antia HM, Lebreton Y, Ong J, Appourchaux T, Bedding TR, Christensen-Dalsgaard J, Creevey O, García RA, Handberg R, Huber D, Kawaler SD, Lund MN, Metcalfe TS, Stassun KG, Bazot M, Beck PG, Bell KJ, Bergemann M, Buzasi DL, Benomar O, Bossini D, Bugnet LA, Campante TL, Orhan ZÇ, Corsaro E, González-Cuesta L, Davies GR, Di Mauro MP, Egeland R, Elsworth YP, Gaulme P, Ghasemi H, Guo Z, Hall OJ, Hasanzadeh A, Hekker S, Howe R, Jenkins JM, Jiménez A, Kiefer R, Kuszlewicz JS, Kallinger T, Latham DW, Lundkvist MS, Mathur S, Montalbán J, Mosser B, Bedón AM, Nielsen MB, Örtel S, Rendle BM, Ricker GR, Rodrigues TS, Roxburgh IW, Safari H, Schofield M, Seager S, Smalley B, Stello D, Szabó R, Tayar J, Themeßl N, Thomas AEL, Vanderspek RK, van Rossem WE, Vrard M, Weiss A, White TR, Winn JN, Yıldız M. 2020. Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi. Nature Astronomy. 4(4), 382–389.","chicago":"Chaplin, William J., Aldo M. Serenelli, Andrea Miglio, Thierry Morel, J. Ted Mackereth, Fiorenzo Vincenzo, Hans Kjeldsen, et al. “Age Dating of an Early Milky Way Merger via Asteroseismology of the Naked-Eye Star ν Indi.” <i>Nature Astronomy</i>. Springer Nature, 2020. <a href=\"https://doi.org/10.1038/s41550-019-0975-9\">https://doi.org/10.1038/s41550-019-0975-9</a>.","apa":"Chaplin, W. J., Serenelli, A. M., Miglio, A., Morel, T., Mackereth, J. T., Vincenzo, F., … Yıldız, M. (2020). Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi. <i>Nature Astronomy</i>. Springer Nature. <a href=\"https://doi.org/10.1038/s41550-019-0975-9\">https://doi.org/10.1038/s41550-019-0975-9</a>","mla":"Chaplin, William J., et al. “Age Dating of an Early Milky Way Merger via Asteroseismology of the Naked-Eye Star ν Indi.” <i>Nature Astronomy</i>, vol. 4, no. 4, Springer Nature, 2020, pp. 382–89, doi:<a href=\"https://doi.org/10.1038/s41550-019-0975-9\">10.1038/s41550-019-0975-9</a>."},"arxiv":1,"month":"04"},{"abstract":[{"lang":"eng","text":"Since the onset of the \"space revolution\" of high-precision high-cadence photometry, asteroseismology has been demonstrated as a powerful tool for informing Galactic archeology investigations. The launch of the NASA Transiting Exoplanet Survey Satellite (TESS) mission has enabled seismic-based inferences to go full sky—providing a clear advantage for large ensemble studies of the different Milky Way components. Here we demonstrate its potential for investigating the Galaxy by carrying out the first asteroseismic ensemble study of red giant stars observed by TESS. We use a sample of 25 stars for which we measure their global asteroseimic observables and estimate their fundamental stellar properties, such as radius, mass, and age. Significant improvements are seen in the uncertainties of our estimates when combining seismic observables from TESS with astrometric measurements from the Gaia mission compared to when the seismology and astrometry are applied separately. Specifically, when combined we show that stellar radii can be determined to a precision of a few percent, masses to 5%–10%, and ages to the 20% level. This is comparable to the precision typically obtained using end-of-mission Kepler data."}],"intvolume":"       889","publication_status":"published","publication_identifier":{"eissn":["1538-4357"],"issn":["0004-637X"]},"author":[{"first_name":"Víctor Silva","last_name":"Aguirre","full_name":"Aguirre, Víctor Silva"},{"first_name":"Dennis","full_name":"Stello, Dennis","last_name":"Stello"},{"first_name":"Amalie","full_name":"Stokholm, Amalie","last_name":"Stokholm"},{"full_name":"Mosumgaard, Jakob R.","last_name":"Mosumgaard","first_name":"Jakob R."},{"last_name":"Ball","full_name":"Ball, Warrick H.","first_name":"Warrick H."},{"first_name":"Sarbani","last_name":"Basu","full_name":"Basu, Sarbani"},{"first_name":"Diego","last_name":"Bossini","full_name":"Bossini, Diego"},{"id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle","last_name":"Bugnet","orcid":"0000-0003-0142-4000","first_name":"Lisa Annabelle"},{"full_name":"Buzasi, Derek","last_name":"Buzasi","first_name":"Derek"},{"full_name":"Campante, Tiago L.","last_name":"Campante","first_name":"Tiago L."},{"first_name":"Lindsey","last_name":"Carboneau","full_name":"Carboneau, Lindsey"},{"full_name":"Chaplin, William J.","last_name":"Chaplin","first_name":"William J."},{"first_name":"Enrico","last_name":"Corsaro","full_name":"Corsaro, Enrico"},{"first_name":"Guy R.","full_name":"Davies, Guy R.","last_name":"Davies"},{"full_name":"Elsworth, Yvonne","last_name":"Elsworth","first_name":"Yvonne"},{"full_name":"García, Rafael A.","last_name":"García","first_name":"Rafael A."},{"full_name":"Gaulme, Patrick","last_name":"Gaulme","first_name":"Patrick"},{"full_name":"Hall, Oliver J.","last_name":"Hall","first_name":"Oliver J."},{"first_name":"Rasmus","full_name":"Handberg, Rasmus","last_name":"Handberg"},{"last_name":"Hon","full_name":"Hon, Marc","first_name":"Marc"},{"full_name":"Kallinger, Thomas","last_name":"Kallinger","first_name":"Thomas"},{"first_name":"Liu","last_name":"Kang","full_name":"Kang, Liu"},{"last_name":"Lund","full_name":"Lund, Mikkel N.","first_name":"Mikkel N."},{"last_name":"Mathur","full_name":"Mathur, Savita","first_name":"Savita"},{"first_name":"Alexey","last_name":"Mints","full_name":"Mints, Alexey"},{"first_name":"Benoit","full_name":"Mosser, Benoit","last_name":"Mosser"},{"first_name":"Zeynep","full_name":"Çelik Orhan, Zeynep","last_name":"Çelik Orhan"},{"last_name":"Rodrigues","full_name":"Rodrigues, Thaíse S.","first_name":"Thaíse S."},{"full_name":"Vrard, Mathieu","last_name":"Vrard","first_name":"Mathieu"},{"full_name":"Yıldız, Mutlu","last_name":"Yıldız","first_name":"Mutlu"},{"first_name":"Joel C.","last_name":"Zinn","full_name":"Zinn, Joel C."},{"first_name":"Sibel","full_name":"Örtel, Sibel","last_name":"Örtel"},{"last_name":"Beck","full_name":"Beck, Paul G.","first_name":"Paul G."},{"last_name":"Bell","full_name":"Bell, Keaton J.","first_name":"Keaton J."},{"first_name":"Zhao","last_name":"Guo","full_name":"Guo, Zhao"},{"first_name":"Chen","last_name":"Jiang","full_name":"Jiang, Chen"},{"first_name":"James S.","last_name":"Kuszlewicz","full_name":"Kuszlewicz, James S."},{"last_name":"Kuehn","full_name":"Kuehn, Charles A.","first_name":"Charles A."},{"last_name":"Li","full_name":"Li, Tanda","first_name":"Tanda"},{"first_name":"Mia S.","last_name":"Lundkvist","full_name":"Lundkvist, Mia S."},{"first_name":"Marc","full_name":"Pinsonneault, Marc","last_name":"Pinsonneault"},{"first_name":"Jamie","full_name":"Tayar, Jamie","last_name":"Tayar"},{"first_name":"Margarida S.","full_name":"Cunha, Margarida S.","last_name":"Cunha"},{"last_name":"Hekker","full_name":"Hekker, Saskia","first_name":"Saskia"},{"first_name":"Daniel","last_name":"Huber","full_name":"Huber, Daniel"},{"full_name":"Miglio, Andrea","last_name":"Miglio","first_name":"Andrea"},{"full_name":"F. G. Monteiro, Mario J. P.","last_name":"F. G. Monteiro","first_name":"Mario J. P."},{"first_name":"Ditte","full_name":"Slumstrup, Ditte","last_name":"Slumstrup"},{"full_name":"Winther, Mark L.","last_name":"Winther","first_name":"Mark L."},{"first_name":"George","full_name":"Angelou, George","last_name":"Angelou"},{"first_name":"Othman","full_name":"Benomar, Othman","last_name":"Benomar"},{"last_name":"Bódi","full_name":"Bódi, Attila","first_name":"Attila"},{"full_name":"De Moura, Bruno L.","last_name":"De Moura","first_name":"Bruno L."},{"first_name":"Sébastien","last_name":"Deheuvels","full_name":"Deheuvels, Sébastien"},{"first_name":"Aliz","last_name":"Derekas","full_name":"Derekas, Aliz"},{"full_name":"Di Mauro, Maria Pia","last_name":"Di Mauro","first_name":"Maria Pia"},{"full_name":"Dupret, Marc-Antoine","last_name":"Dupret","first_name":"Marc-Antoine"},{"full_name":"Jiménez, Antonio","last_name":"Jiménez","first_name":"Antonio"},{"first_name":"Yveline","full_name":"Lebreton, Yveline","last_name":"Lebreton"},{"full_name":"Matthews, Jaymie","last_name":"Matthews","first_name":"Jaymie"},{"full_name":"Nardetto, Nicolas","last_name":"Nardetto","first_name":"Nicolas"},{"full_name":"do Nascimento, Jose D.","last_name":"do Nascimento","first_name":"Jose D."},{"last_name":"Pereira","full_name":"Pereira, Filipe","first_name":"Filipe"},{"full_name":"Rodríguez Díaz, Luisa F.","last_name":"Rodríguez Díaz","first_name":"Luisa F."},{"last_name":"Serenelli","full_name":"Serenelli, Aldo M.","first_name":"Aldo M."},{"full_name":"Spitoni, Emanuele","last_name":"Spitoni","first_name":"Emanuele"},{"last_name":"Stonkutė","full_name":"Stonkutė, Edita","first_name":"Edita"},{"first_name":"Juan Carlos","last_name":"Suárez","full_name":"Suárez, Juan Carlos"},{"first_name":"Robert","full_name":"Szabó, Robert","last_name":"Szabó"},{"full_name":"Van Eylen, Vincent","last_name":"Van Eylen","first_name":"Vincent"},{"first_name":"Rita","last_name":"Ventura","full_name":"Ventura, Rita"},{"first_name":"Kuldeep","last_name":"Verma","full_name":"Verma, Kuldeep"},{"first_name":"Achim","last_name":"Weiss","full_name":"Weiss, Achim"},{"first_name":"Tao","last_name":"Wu","full_name":"Wu, Tao"},{"full_name":"Barclay, Thomas","last_name":"Barclay","first_name":"Thomas"},{"full_name":"Christensen-Dalsgaard, Jørgen","last_name":"Christensen-Dalsgaard","first_name":"Jørgen"},{"first_name":"Jon M.","full_name":"Jenkins, Jon M.","last_name":"Jenkins"},{"full_name":"Kjeldsen, Hans","last_name":"Kjeldsen","first_name":"Hans"},{"first_name":"George R.","last_name":"Ricker","full_name":"Ricker, George R."},{"full_name":"Seager, Sara","last_name":"Seager","first_name":"Sara"},{"first_name":"Roland","full_name":"Vanderspek, Roland","last_name":"Vanderspek"}],"day":"01","scopus_import":"1","title":"Detection and characterization of oscillating red giants: First results from the TESS satellite","oa_version":"Preprint","volume":889,"article_type":"original","date_created":"2022-07-18T13:52:54Z","oa":1,"language":[{"iso":"eng"}],"issue":"2","citation":{"chicago":"Aguirre, Víctor Silva, Dennis Stello, Amalie Stokholm, Jakob R. Mosumgaard, Warrick H. Ball, Sarbani Basu, Diego Bossini, et al. “Detection and Characterization of Oscillating Red Giants: First Results from the TESS Satellite.” <i>The Astrophysical Journal Letters</i>. IOP Publishing, 2020. <a href=\"https://doi.org/10.3847/2041-8213/ab6443\">https://doi.org/10.3847/2041-8213/ab6443</a>.","ista":"Aguirre VS, Stello D, Stokholm A, Mosumgaard JR, Ball WH, Basu S, Bossini D, Bugnet LA, Buzasi D, Campante TL, Carboneau L, Chaplin WJ, Corsaro E, Davies GR, Elsworth Y, García RA, Gaulme P, Hall OJ, Handberg R, Hon M, Kallinger T, Kang L, Lund MN, Mathur S, Mints A, Mosser B, Çelik Orhan Z, Rodrigues TS, Vrard M, Yıldız M, Zinn JC, Örtel S, Beck PG, Bell KJ, Guo Z, Jiang C, Kuszlewicz JS, Kuehn CA, Li T, Lundkvist MS, Pinsonneault M, Tayar J, Cunha MS, Hekker S, Huber D, Miglio A, F. G. Monteiro MJP, Slumstrup D, Winther ML, Angelou G, Benomar O, Bódi A, De Moura BL, Deheuvels S, Derekas A, Di Mauro MP, Dupret M-A, Jiménez A, Lebreton Y, Matthews J, Nardetto N, do Nascimento JD, Pereira F, Rodríguez Díaz LF, Serenelli AM, Spitoni E, Stonkutė E, Suárez JC, Szabó R, Van Eylen V, Ventura R, Verma K, Weiss A, Wu T, Barclay T, Christensen-Dalsgaard J, Jenkins JM, Kjeldsen H, Ricker GR, Seager S, Vanderspek R. 2020. Detection and characterization of oscillating red giants: First results from the TESS satellite. The Astrophysical Journal Letters. 889(2), L34.","mla":"Aguirre, Víctor Silva, et al. “Detection and Characterization of Oscillating Red Giants: First Results from the TESS Satellite.” <i>The Astrophysical Journal Letters</i>, vol. 889, no. 2, L34, IOP Publishing, 2020, doi:<a href=\"https://doi.org/10.3847/2041-8213/ab6443\">10.3847/2041-8213/ab6443</a>.","apa":"Aguirre, V. S., Stello, D., Stokholm, A., Mosumgaard, J. R., Ball, W. H., Basu, S., … Vanderspek, R. (2020). Detection and characterization of oscillating red giants: First results from the TESS satellite. <i>The Astrophysical Journal Letters</i>. IOP Publishing. <a href=\"https://doi.org/10.3847/2041-8213/ab6443\">https://doi.org/10.3847/2041-8213/ab6443</a>","ama":"Aguirre VS, Stello D, Stokholm A, et al. Detection and characterization of oscillating red giants: First results from the TESS satellite. <i>The Astrophysical Journal Letters</i>. 2020;889(2). doi:<a href=\"https://doi.org/10.3847/2041-8213/ab6443\">10.3847/2041-8213/ab6443</a>","short":"V.S. Aguirre, D. Stello, A. Stokholm, J.R. Mosumgaard, W.H. Ball, S. Basu, D. Bossini, L.A. Bugnet, D. Buzasi, T.L. Campante, L. Carboneau, W.J. Chaplin, E. Corsaro, G.R. Davies, Y. Elsworth, R.A. García, P. Gaulme, O.J. Hall, R. Handberg, M. Hon, T. Kallinger, L. Kang, M.N. Lund, S. Mathur, A. Mints, B. Mosser, Z. Çelik Orhan, T.S. Rodrigues, M. Vrard, M. Yıldız, J.C. Zinn, S. Örtel, P.G. Beck, K.J. Bell, Z. Guo, C. Jiang, J.S. Kuszlewicz, C.A. Kuehn, T. Li, M.S. Lundkvist, M. Pinsonneault, J. Tayar, M.S. Cunha, S. Hekker, D. Huber, A. Miglio, M.J.P. F. G. Monteiro, D. Slumstrup, M.L. Winther, G. Angelou, O. Benomar, A. Bódi, B.L. De Moura, S. Deheuvels, A. Derekas, M.P. Di Mauro, M.-A. Dupret, A. Jiménez, Y. Lebreton, J. Matthews, N. Nardetto, J.D. do Nascimento, F. Pereira, L.F. Rodríguez Díaz, A.M. Serenelli, E. Spitoni, E. Stonkutė, J.C. Suárez, R. Szabó, V. Van Eylen, R. Ventura, K. Verma, A. Weiss, T. Wu, T. Barclay, J. Christensen-Dalsgaard, J.M. Jenkins, H. Kjeldsen, G.R. Ricker, S. Seager, R. Vanderspek, The Astrophysical Journal Letters 889 (2020).","ieee":"V. S. Aguirre <i>et al.</i>, “Detection and characterization of oscillating red giants: First results from the TESS satellite,” <i>The Astrophysical Journal Letters</i>, vol. 889, no. 2. IOP Publishing, 2020."},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","month":"02","arxiv":1,"article_number":"L34","main_file_link":[{"url":"https://arxiv.org/abs/1912.07604","open_access":"1"}],"quality_controlled":"1","doi":"10.3847/2041-8213/ab6443","article_processing_charge":"No","publisher":"IOP Publishing","date_updated":"2022-08-22T07:25:51Z","_id":"11612","type":"journal_article","publication":"The Astrophysical Journal Letters","status":"public","extern":"1","acknowledgement":"This Letter includes data collected by the TESS mission, which are publicly available from the Mikulski Archive for Space Telescopes (MAST). Funding for the TESS mission is provided by NASA's Science Mission directorate. Funding for the TESS Asteroseismic Science Operations Centre is provided by the Danish National Research Foundation (grant agreement No. DNRF106), ESA PRODEX (PEA 4000119301), and Stellar Astrophysics Centre (SAC) at Aarhus University. V.S.A. acknowledges support from the Independent Research Fund Denmark (Research grant 7027-00096B). D.B. is supported in the form of work contract FCT/MCTES through national funds and by FEDER through COMPETE2020 in connection to these grants: UID/FIS/04434/2019; PTDC/FIS-AST/30389/2017 & POCI-01-0145-FEDER-030389. L.B., R.A.G., and B.M. acknowledge the support from the CNES/PLATO grant. D.B. acknowledges NASA grant NNX16AB76G. T.L.C. acknowledges support from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 792848 (PULSATION). This work was supported by FCT/MCTES through national funds (UID/FIS/04434/2019). E.C. is funded by the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 664931. R.H. and M.N.L. acknowledge the support of the ESA PRODEX programme. T.S.R. acknowledges financial support from Premiale 2015 MITiC (PI B. Garilli). K.J.B. is supported by the National Science Foundation under Award AST-1903828. M.S.L. is supported by the Carlsberg Foundation (grant agreement No. CF17-0760). M.C. is funded by FCT//MCTES through national funds and by FEDER through COMPETE2020 through these grants: UID/FIS/04434/2019, PTDC/FIS-AST/30389/2017 & POCI-01-0145-FEDER-030389, CEECIND/02619/2017. The research leading to the presented results has received funding from the European Research Council under the European Community's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement no 338251 (StellarAges). A.M. acknowledges support from the European Research Council Consolidator Grant funding scheme (project ASTEROCHRONOMETRY, grant agreement No. 772293, http://www.asterochronometry.eu). A.M.S. is partially supported by MINECO grant ESP2017-82674-R. J.C.S. acknowledges funding support from Spanish public funds for research under projects ESP2017-87676-2-2, and from project RYC-2012-09913 under the 'Ramón y Cajal' program of the Spanish Ministry of Science and Education. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products.","date_published":"2020-02-01T00:00:00Z","year":"2020","external_id":{"arxiv":["1912.07604"]},"keyword":["Space and Planetary Science","Astronomy and Astrophysics"]},{"extern":"1","status":"public","publication":"Dynamics of the Sun and Stars","acknowledgement":"The authors of this work acknowledge the support received from the PLATO CNES grant, the National Aeronautics and Space Administration under Grant NNX15AF13G, by the National Science Foundation grant AST-1411685, the Ramon y Cajal fellowship number RYC-2015-17697, the ERC SPIRE grant (647383), and the Fundation L’Oréal-Unesco-Académie des sciences.","date_published":"2020-12-19T00:00:00Z","year":"2020","external_id":{"arxiv":["2012.08684"]},"page":"251-257","main_file_link":[{"url":"https://arxiv.org/abs/2012.08684","open_access":"1"}],"quality_controlled":"1","doi":"10.1007/978-3-030-55336-4_33","article_processing_charge":"No","alternative_title":["Astrophysics and Space Science Proceedings"],"editor":[{"last_name":"Monteiro","full_name":"Monteiro, Mario","first_name":"Mario"},{"first_name":"Rafael A","full_name":"Garcia, Rafael A","last_name":"Garcia"},{"first_name":"Jorgen","full_name":"Christensen-Dalsgaard, Jorgen","last_name":"Christensen-Dalsgaard"},{"full_name":"McIntosh, Scott W","last_name":"McIntosh","first_name":"Scott W"}],"publisher":"Springer Nature","date_updated":"2022-08-22T08:07:42Z","edition":"1","_id":"11622","type":"book_chapter","series_title":"ASSSP","oa":1,"language":[{"iso":"eng"}],"place":"Cham","citation":{"ista":"Bugnet LA, Prat V, Mathis S, García RA, Mathur S, Augustson K, Neiner C, Thompson MJ. 2020.The impact of a fossil magnetic field on dipolar mixed-mode frequencies in sub- and red-giant stars. In: Dynamics of the Sun and Stars. Astrophysics and Space Science Proceedings, vol. 57, 251–257.","chicago":"Bugnet, Lisa Annabelle, V. Prat, S. Mathis, R. A. García, S. Mathur, K. Augustson, C. Neiner, and M. J. Thompson. “The Impact of a Fossil Magnetic Field on Dipolar Mixed-Mode Frequencies in Sub- and Red-Giant Stars.” In <i>Dynamics of the Sun and Stars</i>, edited by Mario Monteiro, Rafael A Garcia, Jorgen Christensen-Dalsgaard, and Scott W McIntosh, 1st ed., 57:251–57. ASSSP. Cham: Springer Nature, 2020. <a href=\"https://doi.org/10.1007/978-3-030-55336-4_33\">https://doi.org/10.1007/978-3-030-55336-4_33</a>.","mla":"Bugnet, Lisa Annabelle, et al. “The Impact of a Fossil Magnetic Field on Dipolar Mixed-Mode Frequencies in Sub- and Red-Giant Stars.” <i>Dynamics of the Sun and Stars</i>, edited by Mario Monteiro et al., 1st ed., vol. 57, Springer Nature, 2020, pp. 251–57, doi:<a href=\"https://doi.org/10.1007/978-3-030-55336-4_33\">10.1007/978-3-030-55336-4_33</a>.","apa":"Bugnet, L. A., Prat, V., Mathis, S., García, R. A., Mathur, S., Augustson, K., … Thompson, M. J. (2020). The impact of a fossil magnetic field on dipolar mixed-mode frequencies in sub- and red-giant stars. In M. Monteiro, R. A. Garcia, J. Christensen-Dalsgaard, &#38; S. W. McIntosh (Eds.), <i>Dynamics of the Sun and Stars</i> (1st ed., Vol. 57, pp. 251–257). Cham: Springer Nature. <a href=\"https://doi.org/10.1007/978-3-030-55336-4_33\">https://doi.org/10.1007/978-3-030-55336-4_33</a>","ama":"Bugnet LA, Prat V, Mathis S, et al. The impact of a fossil magnetic field on dipolar mixed-mode frequencies in sub- and red-giant stars. In: Monteiro M, Garcia RA, Christensen-Dalsgaard J, McIntosh SW, eds. <i>Dynamics of the Sun and Stars</i>. Vol 57. 1st ed. ASSSP. Cham: Springer Nature; 2020:251-257. doi:<a href=\"https://doi.org/10.1007/978-3-030-55336-4_33\">10.1007/978-3-030-55336-4_33</a>","short":"L.A. Bugnet, V. Prat, S. Mathis, R.A. García, S. Mathur, K. Augustson, C. Neiner, M.J. Thompson, in:, M. Monteiro, R.A. Garcia, J. Christensen-Dalsgaard, S.W. McIntosh (Eds.), Dynamics of the Sun and Stars, 1st ed., Springer Nature, Cham, 2020, pp. 251–257.","ieee":"L. A. Bugnet <i>et al.</i>, “The impact of a fossil magnetic field on dipolar mixed-mode frequencies in sub- and red-giant stars,” in <i>Dynamics of the Sun and Stars</i>, 1st ed., vol. 57, M. Monteiro, R. A. Garcia, J. Christensen-Dalsgaard, and S. W. McIntosh, Eds. Cham: Springer Nature, 2020, pp. 251–257."},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","month":"12","arxiv":1,"intvolume":"        57","abstract":[{"lang":"eng","text":"The recent discovery of low-amplitude dipolar oscillation mixed modes in massive red giants indicates the presence of a missing physical process inside their cores. Stars more massive than ∼ 1.3 M⊙ are known to develop a convective core during the main-sequence: the dynamo process triggered by this convection could be the origin of a strong magnetic field inside the core of the star, trapped when it becomes stably stratified and for the rest of its evolution. The presence of highly magnetized white dwarfs strengthens the hypothesis of buried fossil magnetic fields inside the core of evolved low-mass stars. If such a fossil field exists, it should affect the mixed modes of red giants as they are sensitive to processes affecting the deepest layers of these stars. The impact of a magnetic field on dipolar oscillations modes was one of Pr. Michael J. Thompson’s research topics during the 90s when preparing the helioseismic SoHO space mission. As the detection of gravity modes in the Sun is still controversial, the investigation of the solar oscillation modes did not provide any hint of the existence of a magnetic field in the solar radiative core. Today we have access to the core of evolved stars thanks to the asteroseismic observation of mixed modes from CoRoT, Kepler, K2 and TESS missions. The idea of applying and generalizing the work done for the Sun came from discussions with Pr. Michael Thompson in early 2018 before we lost him. Following the path we drew together, we theoretically investigate the effect of a stable axisymmetric mixed poloidal and toroidal magnetic field, aligned with the rotation axis of the star, on the mixed modes frequencies of a typical evolved low-mass star. This enables us to estimate the magnetic perturbations to the eigenfrequencies of mixed dipolar modes, depending on the magnetic field strength and the evolutionary state of the star. We conclude that strong magnetic fields of ∼ 1MG should perturb the mixed-mode frequency pattern enough for its effects to be detectable inside current asteroseismic data."}],"publication_identifier":{"eissn":["1570-6605"],"eisbn":["978-3-030-55336-4"],"isbn":["978-3-030-55335-7"],"issn":["1570-6591"]},"publication_status":"published","author":[{"last_name":"Bugnet","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle","orcid":"0000-0003-0142-4000","first_name":"Lisa Annabelle"},{"first_name":"V.","full_name":"Prat, V.","last_name":"Prat"},{"full_name":"Mathis, S.","last_name":"Mathis","first_name":"S."},{"first_name":"R. A.","last_name":"García","full_name":"García, R. A."},{"full_name":"Mathur, S.","last_name":"Mathur","first_name":"S."},{"first_name":"K.","last_name":"Augustson","full_name":"Augustson, K."},{"first_name":"C.","last_name":"Neiner","full_name":"Neiner, C."},{"full_name":"Thompson, M. J.","last_name":"Thompson","first_name":"M. J."}],"scopus_import":"1","day":"19","oa_version":"Preprint","title":"The impact of a fossil magnetic field on dipolar mixed-mode frequencies in sub- and red-giant stars","volume":57,"date_created":"2022-07-19T08:25:41Z"},{"month":"07","arxiv":1,"article_number":"46","language":[{"iso":"eng"}],"oa":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","citation":{"ama":"Mathur S, García RA, Bugnet LA, Santos ÂRG, Santiago N, Beck PG. Revisiting the impact of stellar magnetic activity on the detectability of solar-like oscillations by Kepler. <i>Frontiers in Astronomy and Space Sciences</i>. 2019;6. doi:<a href=\"https://doi.org/10.3389/fspas.2019.00046\">10.3389/fspas.2019.00046</a>","ieee":"S. Mathur, R. A. García, L. A. Bugnet, Â. R. G. Santos, N. Santiago, and P. G. Beck, “Revisiting the impact of stellar magnetic activity on the detectability of solar-like oscillations by Kepler,” <i>Frontiers in Astronomy and Space Sciences</i>, vol. 6. Frontiers Media, 2019.","short":"S. Mathur, R.A. García, L.A. Bugnet, Â.R.G. Santos, N. Santiago, P.G. Beck, Frontiers in Astronomy and Space Sciences 6 (2019).","chicago":"Mathur, Savita, Rafael A. García, Lisa Annabelle Bugnet, Ângela R.G. Santos, Netsha Santiago, and Paul G. Beck. “Revisiting the Impact of Stellar Magnetic Activity on the Detectability of Solar-like Oscillations by Kepler.” <i>Frontiers in Astronomy and Space Sciences</i>. Frontiers Media, 2019. <a href=\"https://doi.org/10.3389/fspas.2019.00046\">https://doi.org/10.3389/fspas.2019.00046</a>.","ista":"Mathur S, García RA, Bugnet LA, Santos ÂRG, Santiago N, Beck PG. 2019. Revisiting the impact of stellar magnetic activity on the detectability of solar-like oscillations by Kepler. Frontiers in Astronomy and Space Sciences. 6, 46.","apa":"Mathur, S., García, R. A., Bugnet, L. A., Santos, Â. R. G., Santiago, N., &#38; Beck, P. G. (2019). Revisiting the impact of stellar magnetic activity on the detectability of solar-like oscillations by Kepler. <i>Frontiers in Astronomy and Space Sciences</i>. Frontiers Media. <a href=\"https://doi.org/10.3389/fspas.2019.00046\">https://doi.org/10.3389/fspas.2019.00046</a>","mla":"Mathur, Savita, et al. “Revisiting the Impact of Stellar Magnetic Activity on the Detectability of Solar-like Oscillations by Kepler.” <i>Frontiers in Astronomy and Space Sciences</i>, vol. 6, 46, Frontiers Media, 2019, doi:<a href=\"https://doi.org/10.3389/fspas.2019.00046\">10.3389/fspas.2019.00046</a>."},"title":"Revisiting the impact of stellar magnetic activity on the detectability of solar-like oscillations by Kepler","oa_version":"Preprint","day":"10","scopus_import":"1","author":[{"first_name":"Savita","full_name":"Mathur, Savita","last_name":"Mathur"},{"first_name":"Rafael A.","last_name":"García","full_name":"García, Rafael A."},{"last_name":"Bugnet","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle","first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000"},{"first_name":"Ângela R.G.","last_name":"Santos","full_name":"Santos, Ângela R.G."},{"first_name":"Netsha","last_name":"Santiago","full_name":"Santiago, Netsha"},{"first_name":"Paul G.","last_name":"Beck","full_name":"Beck, Paul G."}],"date_created":"2022-07-18T14:00:36Z","article_type":"original","volume":6,"intvolume":"         6","abstract":[{"text":"Over 2,000 stars were observed for 1 month with a high enough cadence in order to look for acoustic modes during the survey phase of the Kepler mission. Solar-like oscillations have been detected in about 540 stars. The question of why no oscillations were detected in the remaining stars is still open. Previous works explained the non-detection of modes with the high level of magnetic activity of the stars. However, the sample of stars studied contained some classical pulsators and red giants that could have biased the results. In this work, we revisit this analysis on a cleaner sample of main-sequence solar-like stars that consists of 1,014 stars. First we compute the predicted amplitude of the modes of that sample and for the stars with detected oscillation and compare it to the noise at high frequency in the power spectrum. We find that the stars with detected modes have an amplitude to noise ratio larger than 0.94. We measure reliable rotation periods and the associated photometric magnetic index for 684 stars out of the full sample and in particular for 323 stars where the amplitude of the modes is predicted to be high enough to be detected. We find that among these 323 stars 32% of them have a level of magnetic activity larger than the Sun during its maximum activity, explaining the non-detection of acoustic modes. Interestingly, magnetic activity cannot be the primary reason responsible for the absence of detectable modes in the remaining 68% of the stars without acoustic modes detected and with reliable rotation periods. Thus, we investigate metallicity, inclination angle of the rotation axis, and binarity as possible causes of low mode amplitudes. Using spectroscopic observations for a subsample, we find that a low metallicity could be the reason for suppressed modes. No clear correlation with binarity nor inclination is found. We also derive the lower limit for our photometric activity index (of 20–30 ppm) below which rotation and magnetic activity are not detected. Finally, with our analysis we conclude that stars with a photometric activity index larger than 2,000 ppm have 98.3% probability of not having oscillations detected.","lang":"eng"}],"publication_status":"published","publication_identifier":{"eissn":["2296-987X"]},"external_id":{"arxiv":["1907.01415"]},"year":"2019","keyword":["Astronomy and Astrophysics"],"extern":"1","publication":"Frontiers in Astronomy and Space Sciences","status":"public","acknowledgement":"This paper includes data collected by the Kepler mission. Funding for the Kepler mission is provided by the NASA Science Mission directorate. Some of the data presented in this paper were obtained from the Mikulski Archive for Space Telescopes (MAST). STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. Partly Based on observations obtained with the HERMES spectrograph on the Mercator Telescope, which was supported by the Research Foundation—Flanders (FWO), Belgium, the Research Council of KU Leuven, Belgium, the Fonds National de la Recherche Scientifique (F.R.S.-FNRS), Belgium, the Royal Observatory of Belgium, the Observatoire de Genève, Switzerland, and the Thüringer Landessternwarte Tautenburg, Germany. SM acknowledges support by the National Aeronautics and Space Administration under Grant NNX15AF13G, by the National Science Foundation grant AST-1411685, and the Ramon y Cajal fellowship number RYC-2015-17697. RG acknowledges the support from PLATO and GOLF CNES grants. ÂS acknowledges the support from National Aeronautics and Space Administration under Grant NNX17AF27G. PB acknowledges the support of the MINECO under the fellowship program Juan de la Cierva Incorporacion (IJCI-2015-26034).","date_published":"2019-07-10T00:00:00Z","publisher":"Frontiers Media","article_processing_charge":"No","doi":"10.3389/fspas.2019.00046","type":"journal_article","_id":"11613","date_updated":"2022-08-22T07:29:55Z","quality_controlled":"1","main_file_link":[{"url":"https://arxiv.org/abs/1907.01415","open_access":"1"}]},{"acknowledgement":"We thank the enitre T’DA team for useful comments and discussions, in particular Andrew Tkachenko. We also acknowledge Marc Hon, Keaton Bell, and James Kuszlewicz for useful comments on the manuscript. L.B. and R.A.G. acknowledge the support from PLATO and GOLF CNES grants. S.M. acknowledges support by the Ramon y Cajal fellowship number RYC-2015-17697. O.J.H. and B.M.R. acknowledge the support of the UK Science and Technology Facilities Council (STFC). M.N.L. acknowledges the support of the ESA PRODEX programme (PEA 4000119301). Funding for the Stellar Astrophysics Centre is provided by the Danish National Research Foundation (Grant DNRF106).","date_published":"2019-04-19T00:00:00Z","publication":"Astronomy & Astrophysics","status":"public","extern":"1","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"external_id":{"arxiv":["1902.09854"]},"year":"2019","quality_controlled":"1","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/1902.09854"}],"type":"journal_article","_id":"11614","date_updated":"2022-08-22T07:32:51Z","publisher":"EDP Science","article_processing_charge":"No","doi":"10.1051/0004-6361/201834780","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","citation":{"ista":"Bugnet LA, García RA, Mathur S, Davies GR, Hall OJ, Lund MN, Rendle BM. 2019. FliPerClass: In search of solar-like pulsators among TESS targets. Astronomy &#38; Astrophysics. 624, A79.","chicago":"Bugnet, Lisa Annabelle, R. A. García, S. Mathur, G. R. Davies, O. J. Hall, M. N. Lund, and B. M. Rendle. “FliPerClass: In Search of Solar-like Pulsators among TESS Targets.” <i>Astronomy &#38; Astrophysics</i>. EDP Science, 2019. <a href=\"https://doi.org/10.1051/0004-6361/201834780\">https://doi.org/10.1051/0004-6361/201834780</a>.","apa":"Bugnet, L. A., García, R. A., Mathur, S., Davies, G. R., Hall, O. J., Lund, M. N., &#38; Rendle, B. M. (2019). FliPerClass: In search of solar-like pulsators among TESS targets. <i>Astronomy &#38; Astrophysics</i>. EDP Science. <a href=\"https://doi.org/10.1051/0004-6361/201834780\">https://doi.org/10.1051/0004-6361/201834780</a>","mla":"Bugnet, Lisa Annabelle, et al. “FliPerClass: In Search of Solar-like Pulsators among TESS Targets.” <i>Astronomy &#38; Astrophysics</i>, vol. 624, A79, EDP Science, 2019, doi:<a href=\"https://doi.org/10.1051/0004-6361/201834780\">10.1051/0004-6361/201834780</a>.","ama":"Bugnet LA, García RA, Mathur S, et al. FliPerClass: In search of solar-like pulsators among TESS targets. <i>Astronomy &#38; Astrophysics</i>. 2019;624. doi:<a href=\"https://doi.org/10.1051/0004-6361/201834780\">10.1051/0004-6361/201834780</a>","ieee":"L. A. Bugnet <i>et al.</i>, “FliPerClass: In search of solar-like pulsators among TESS targets,” <i>Astronomy &#38; Astrophysics</i>, vol. 624. EDP Science, 2019.","short":"L.A. Bugnet, R.A. García, S. Mathur, G.R. Davies, O.J. Hall, M.N. Lund, B.M. Rendle, Astronomy &#38; Astrophysics 624 (2019)."},"language":[{"iso":"eng"}],"oa":1,"article_number":"A79","arxiv":1,"month":"04","publication_status":"published","publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"intvolume":"       624","abstract":[{"lang":"eng","text":"The NASA Transiting Exoplanet Survey Satellite (TESS) is about to provide full-frame images of almost the entire sky. The amount of stellar data to be analysed represents hundreds of millions stars, which is several orders of magnitude more than the number of stars observed by the Convection, Rotation and planetary Transits satellite (CoRoT), and NASA Kepler and K2 missions. We aim at automatically classifying the newly observed stars with near real-time algorithms to better guide the subsequent detailed studies. In this paper, we present a classification algorithm built to recognise solar-like pulsators among classical pulsators. This algorithm relies on the global amount of power contained in the power spectral density (PSD), also known as the flicker in spectral power density (FliPer). Because each type of pulsating star has a characteristic background or pulsation pattern, the shape of the PSD at different frequencies can be used to characterise the type of pulsating star. The FliPer classifier (FliPerClass) uses different FliPer parameters along with the effective temperature as input parameters to feed a ML algorithm in order to automatically classify the pulsating stars observed by TESS. Using noisy TESS-simulated data from the TESS Asteroseismic Science Consortium (TASC), we classify pulsators with a 98% accuracy. Among them, solar-like pulsating stars are recognised with a 99% accuracy, which is of great interest for a further seismic analysis of these stars, which are like our Sun. Similar results are obtained when we trained our classifier and applied it to 27-day subsets of real Kepler data. FliPerClass is part of the large TASC classification pipeline developed by the TESS Data for Asteroseismology (T’DA) classification working group."}],"date_created":"2022-07-18T14:13:34Z","article_type":"original","volume":624,"title":"FliPerClass: In search of solar-like pulsators among TESS targets","oa_version":"Preprint","scopus_import":"1","day":"19","author":[{"first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000","id":"d9edb345-f866-11ec-9b37-d119b5234501","full_name":"Bugnet, Lisa Annabelle","last_name":"Bugnet"},{"full_name":"García, R. A.","last_name":"García","first_name":"R. A."},{"full_name":"Mathur, S.","last_name":"Mathur","first_name":"S."},{"full_name":"Davies, G. R.","last_name":"Davies","first_name":"G. R."},{"first_name":"O. J.","full_name":"Hall, O. J.","last_name":"Hall"},{"full_name":"Lund, M. N.","last_name":"Lund","first_name":"M. N."},{"first_name":"B. M.","last_name":"Rendle","full_name":"Rendle, B. M."}]},{"author":[{"first_name":"Marc","full_name":"Hon, Marc","last_name":"Hon"},{"first_name":"Dennis","last_name":"Stello","full_name":"Stello, Dennis"},{"first_name":"Rafael A","last_name":"García","full_name":"García, Rafael A"},{"first_name":"Savita","full_name":"Mathur, Savita","last_name":"Mathur"},{"last_name":"Sharma","full_name":"Sharma, Sanjib","first_name":"Sanjib"},{"first_name":"Isabel L","full_name":"Colman, Isabel L","last_name":"Colman"},{"first_name":"Lisa Annabelle","orcid":"0000-0003-0142-4000","last_name":"Bugnet","full_name":"Bugnet, Lisa Annabelle","id":"d9edb345-f866-11ec-9b37-d119b5234501"}],"day":"01","scopus_import":"1","title":"A search for red giant solar-like oscillations in all Kepler data","oa_version":"Preprint","volume":485,"article_type":"original","date_created":"2022-07-18T14:26:03Z","intvolume":"       485","abstract":[{"lang":"eng","text":"The recently published Kepler mission Data Release 25 (DR25) reported on ∼197 000 targets observed during the mission. Despite this, no wide search for red giants showing solar-like oscillations have been made across all stars observed in Kepler’s long-cadence mode. In this work, we perform this task using custom apertures on the Kepler pixel files and detect oscillations in 21 914 stars, representing the largest sample of solar-like oscillating stars to date. We measure their frequency at maximum power, νmax, down to νmax≃4μHz and obtain log (g) estimates with a typical uncertainty below 0.05 dex, which is superior to typical measurements from spectroscopy. Additionally, the νmax distribution of our detections show good agreement with results from a simulated model of the Milky Way, with a ratio of observed to predicted stars of 0.992 for stars with 10<νmax<270μHz. Among our red giant detections, we find 909 to be dwarf/subgiant stars whose flux signal is polluted by a neighbouring giant as a result of using larger photometric apertures than those used by the NASA Kepler science processing pipeline. We further find that only 293 of the polluting giants are known Kepler targets. The remainder comprises over 600 newly identified oscillating red giants, with many expected to belong to the Galactic halo, serendipitously falling within the Kepler pixel files of targeted stars."}],"publication_identifier":{"eissn":["1365-2966"],"issn":["0035-8711"]},"publication_status":"published","arxiv":1,"month":"06","oa":1,"language":[{"iso":"eng"}],"issue":"4","citation":{"ieee":"M. Hon <i>et al.</i>, “A search for red giant solar-like oscillations in all Kepler data,” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 485, no. 4. Oxford University Press, pp. 5616–5630, 2019.","short":"M. Hon, D. Stello, R.A. García, S. Mathur, S. Sharma, I.L. Colman, L.A. Bugnet, Monthly Notices of the Royal Astronomical Society 485 (2019) 5616–5630.","ama":"Hon M, Stello D, García RA, et al. A search for red giant solar-like oscillations in all Kepler data. <i>Monthly Notices of the Royal Astronomical Society</i>. 2019;485(4):5616-5630. doi:<a href=\"https://doi.org/10.1093/mnras/stz622\">10.1093/mnras/stz622</a>","apa":"Hon, M., Stello, D., García, R. A., Mathur, S., Sharma, S., Colman, I. L., &#38; Bugnet, L. A. (2019). A search for red giant solar-like oscillations in all Kepler data. <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/mnras/stz622\">https://doi.org/10.1093/mnras/stz622</a>","mla":"Hon, Marc, et al. “A Search for Red Giant Solar-like Oscillations in All Kepler Data.” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 485, no. 4, Oxford University Press, 2019, pp. 5616–30, doi:<a href=\"https://doi.org/10.1093/mnras/stz622\">10.1093/mnras/stz622</a>.","ista":"Hon M, Stello D, García RA, Mathur S, Sharma S, Colman IL, Bugnet LA. 2019. A search for red giant solar-like oscillations in all Kepler data. Monthly Notices of the Royal Astronomical Society. 485(4), 5616–5630.","chicago":"Hon, Marc, Dennis Stello, Rafael A García, Savita Mathur, Sanjib Sharma, Isabel L Colman, and Lisa Annabelle Bugnet. “A Search for Red Giant Solar-like Oscillations in All Kepler Data.” <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press, 2019. <a href=\"https://doi.org/10.1093/mnras/stz622\">https://doi.org/10.1093/mnras/stz622</a>."},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","doi":"10.1093/mnras/stz622","article_processing_charge":"No","publisher":"Oxford University Press","date_updated":"2022-08-22T07:35:19Z","_id":"11615","type":"journal_article","page":"5616-5630","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/1903.00115"}],"quality_controlled":"1","year":"2019","external_id":{"arxiv":["1903.00115"]},"keyword":["Space and Planetary Science","Astronomy and Astrophysics","asteroseismology","methods: data analysis","techniques: image processing","stars: oscillations","stars: statistics"],"publication":"Monthly Notices of the Royal Astronomical Society","extern":"1","status":"public","acknowledgement":"Funding for this Discovery mission is provided by NASA’s Science mission Directorate. We thank the entire Kepler team without whom this investigation would not be possible. DS is the recipient of an Australian Research Council Future Fellowship (project number FT1400147). RAG acknowledges the support from CNES. SM acknowledges support from NASA grant NNX15AF13G, NSF grant AST-1411685, and the Ramon y Cajal fellowship number RYC-2015-17697. ILC acknowledges scholarship support from the University of Sydney. We would like to thank Nicholas Barbara and Timothy Bedding for providing us with a list of variable stars that helped to validate a number of detections in this study. We also thank the group at the University of Sydney for fruitful discussions. Finally, we gratefully acknowledge the support of NVIDIA Corporation with the donation of the Titan Xp GPU used for this research.","date_published":"2019-06-01T00:00:00Z"}]