[{"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"language":[{"iso":"eng"}],"issue":"1044","publication_identifier":{"eissn":["1538-3873"],"issn":["0004-6280"]},"doi":"10.1088/1538-3873/acb6b5","quality_controlled":"1","publisher":"IOP Publishing","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publication":"Publications of the Astronomical Society of the Pacific","scopus_import":"1","article_processing_charge":"No","article_type":"original","author":[{"full_name":"Geen, Sam","last_name":"Geen","first_name":"Sam"},{"full_name":"Agrawal, Poojan","last_name":"Agrawal","first_name":"Poojan"},{"full_name":"Crowther, Paul A.","first_name":"Paul A.","last_name":"Crowther"},{"full_name":"Keller, B. W.","last_name":"Keller","first_name":"B. W."},{"last_name":"de Koter","first_name":"Alex","full_name":"de Koter, Alex"},{"last_name":"Keszthelyi","first_name":"Zsolt","full_name":"Keszthelyi, Zsolt"},{"full_name":"van de Voort, Freeke","last_name":"van de Voort","first_name":"Freeke"},{"full_name":"Ali, Ahmad A.","last_name":"Ali","first_name":"Ahmad A."},{"last_name":"Backs","first_name":"Frank","full_name":"Backs, Frank"},{"full_name":"Bonne, Lars","first_name":"Lars","last_name":"Bonne"},{"first_name":"Vittoria","last_name":"Brugaletta","full_name":"Brugaletta, Vittoria"},{"full_name":"Derkink, Annelotte","first_name":"Annelotte","last_name":"Derkink"},{"first_name":"Sylvia","last_name":"Ekström","full_name":"Ekström, Sylvia"},{"full_name":"Fichtner, Yvonne A.","last_name":"Fichtner","first_name":"Yvonne A."},{"last_name":"Grassitelli","first_name":"Luca","full_name":"Grassitelli, Luca"},{"full_name":"Götberg, Ylva Louise Linsdotter","orcid":"0000-0002-6960-6911","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","first_name":"Ylva Louise Linsdotter","last_name":"Götberg"},{"first_name":"Erin R.","last_name":"Higgins","full_name":"Higgins, Erin R."},{"first_name":"Eva","last_name":"Laplace","full_name":"Laplace, Eva"},{"full_name":"You Liow, Kong","last_name":"You Liow","first_name":"Kong"},{"first_name":"Marta","last_name":"Lorenzo","full_name":"Lorenzo, Marta"},{"first_name":"Anna F.","last_name":"McLeod","full_name":"McLeod, Anna F."},{"full_name":"Meynet, Georges","last_name":"Meynet","first_name":"Georges"},{"full_name":"Newsome, Megan","last_name":"Newsome","first_name":"Megan"},{"first_name":"G.","last_name":"André Oliva","full_name":"André Oliva, G."},{"full_name":"Ramachandran, Varsha","last_name":"Ramachandran","first_name":"Varsha"},{"first_name":"Martin P.","last_name":"Rey","full_name":"Rey, Martin P."},{"last_name":"Rieder","first_name":"Steven","full_name":"Rieder, Steven"},{"first_name":"Emilio","last_name":"Romano-Díaz","full_name":"Romano-Díaz, Emilio"},{"last_name":"Sabhahit","first_name":"Gautham","full_name":"Sabhahit, Gautham"},{"full_name":"Sander, Andreas A. C.","first_name":"Andreas A. C.","last_name":"Sander"},{"last_name":"Sarwar","first_name":"Rafia","full_name":"Sarwar, Rafia"},{"first_name":"Hanno","last_name":"Stinshoff","full_name":"Stinshoff, Hanno"},{"first_name":"Mitchel","last_name":"Stoop","full_name":"Stoop, Mitchel"},{"full_name":"Szécsi, Dorottya","first_name":"Dorottya","last_name":"Szécsi"},{"last_name":"Trebitsch","first_name":"Maxime","full_name":"Trebitsch, Maxime"},{"full_name":"Vink, Jorick S.","first_name":"Jorick S.","last_name":"Vink"},{"first_name":"Ethan","last_name":"Winch","full_name":"Winch, Ethan"}],"day":"09","arxiv":1,"title":"Bringing stellar evolution and feedback together: Summary of proposals from the Lorentz Center workshop","article_number":"021001","external_id":{"arxiv":["2301.13611"]},"status":"public","intvolume":"       135","extern":"1","citation":{"short":"S. Geen, P. Agrawal, P.A. Crowther, B.W. Keller, A. de Koter, Z. Keszthelyi, F. van de Voort, A.A. Ali, F. Backs, L. Bonne, V. Brugaletta, A. Derkink, S. Ekström, Y.A. Fichtner, L. Grassitelli, Y.L.L. Götberg, E.R. Higgins, E. Laplace, K. You Liow, M. Lorenzo, A.F. McLeod, G. Meynet, M. Newsome, G. André Oliva, V. Ramachandran, M.P. Rey, S. Rieder, E. Romano-Díaz, G. Sabhahit, A.A.C. Sander, R. Sarwar, H. Stinshoff, M. Stoop, D. Szécsi, M. Trebitsch, J.S. Vink, E. Winch, Publications of the Astronomical Society of the Pacific 135 (2023).","ieee":"S. Geen <i>et al.</i>, “Bringing stellar evolution and feedback together: Summary of proposals from the Lorentz Center workshop,” <i>Publications of the Astronomical Society of the Pacific</i>, vol. 135, no. 1044. IOP Publishing, 2023.","chicago":"Geen, Sam, Poojan Agrawal, Paul A. Crowther, B. W. Keller, Alex de Koter, Zsolt Keszthelyi, Freeke van de Voort, et al. “Bringing Stellar Evolution and Feedback Together: Summary of Proposals from the Lorentz Center Workshop.” <i>Publications of the Astronomical Society of the Pacific</i>. IOP Publishing, 2023. <a href=\"https://doi.org/10.1088/1538-3873/acb6b5\">https://doi.org/10.1088/1538-3873/acb6b5</a>.","ista":"Geen S, Agrawal P, Crowther PA, Keller BW, de Koter A, Keszthelyi Z, van de Voort F, Ali AA, Backs F, Bonne L, Brugaletta V, Derkink A, Ekström S, Fichtner YA, Grassitelli L, Götberg YLL, Higgins ER, Laplace E, You Liow K, Lorenzo M, McLeod AF, Meynet G, Newsome M, André Oliva G, Ramachandran V, Rey MP, Rieder S, Romano-Díaz E, Sabhahit G, Sander AAC, Sarwar R, Stinshoff H, Stoop M, Szécsi D, Trebitsch M, Vink JS, Winch E. 2023. Bringing stellar evolution and feedback together: Summary of proposals from the Lorentz Center workshop. Publications of the Astronomical Society of the Pacific. 135(1044), 021001.","mla":"Geen, Sam, et al. “Bringing Stellar Evolution and Feedback Together: Summary of Proposals from the Lorentz Center Workshop.” <i>Publications of the Astronomical Society of the Pacific</i>, vol. 135, no. 1044, 021001, IOP Publishing, 2023, doi:<a href=\"https://doi.org/10.1088/1538-3873/acb6b5\">10.1088/1538-3873/acb6b5</a>.","apa":"Geen, S., Agrawal, P., Crowther, P. A., Keller, B. W., de Koter, A., Keszthelyi, Z., … Winch, E. (2023). Bringing stellar evolution and feedback together: Summary of proposals from the Lorentz Center workshop. <i>Publications of the Astronomical Society of the Pacific</i>. IOP Publishing. <a href=\"https://doi.org/10.1088/1538-3873/acb6b5\">https://doi.org/10.1088/1538-3873/acb6b5</a>","ama":"Geen S, Agrawal P, Crowther PA, et al. Bringing stellar evolution and feedback together: Summary of proposals from the Lorentz Center workshop. <i>Publications of the Astronomical Society of the Pacific</i>. 2023;135(1044). doi:<a href=\"https://doi.org/10.1088/1538-3873/acb6b5\">10.1088/1538-3873/acb6b5</a>"},"oa":1,"publication_status":"published","date_published":"2023-03-09T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://doi.org/10.1088/1538-3873/acb6b5"}],"year":"2023","_id":"13449","abstract":[{"lang":"eng","text":"Stars strongly impact their environment, and shape structures on all scales throughout the universe, in a process known as \"feedback.\" Due to the complexity of both stellar evolution and the physics of larger astrophysical structures, there remain many unanswered questions about how feedback operates and what we can learn about stars by studying their imprint on the wider universe. In this white paper, we summarize discussions from the Lorentz Center meeting \"Bringing Stellar Evolution and Feedback Together\" in 2022 April and identify key areas where further dialog can bring about radical changes in how we view the relationship between stars and the universe they live in."}],"date_updated":"2023-08-21T12:09:14Z","month":"03","oa_version":"Published Version","type":"journal_article","volume":135,"date_created":"2023-08-03T10:09:57Z"},{"publisher":"American Astronomical Society","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_type":"original","article_processing_charge":"No","scopus_import":"1","publication":"The Astrophysical Journal","day":"20","author":[{"full_name":"O‘Grady, Anna J. G.","last_name":"O‘Grady","first_name":"Anna J. G."},{"first_name":"Maria R.","last_name":"Drout","full_name":"Drout, Maria R."},{"last_name":"Gaensler","first_name":"B. M.","full_name":"Gaensler, B. M."},{"full_name":"Kochanek, C. S.","last_name":"Kochanek","first_name":"C. S."},{"full_name":"Neugent, Kathryn F.","first_name":"Kathryn F.","last_name":"Neugent"},{"full_name":"Doherty, Carolyn L.","last_name":"Doherty","first_name":"Carolyn L."},{"full_name":"Speagle, Joshua S.","first_name":"Joshua S.","last_name":"Speagle"},{"last_name":"Shappee","first_name":"B. J.","full_name":"Shappee, B. J."},{"last_name":"Rauch","first_name":"Michael","full_name":"Rauch, Michael"},{"last_name":"Götberg","first_name":"Ylva Louise Linsdotter","full_name":"Götberg, Ylva Louise Linsdotter","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911"},{"first_name":"Bethany","last_name":"Ludwig","full_name":"Ludwig, Bethany"},{"full_name":"Thompson, Todd A.","last_name":"Thompson","first_name":"Todd A."}],"article_number":"18","title":"Cool, luminous, and highly variable stars in the Magellanic Clouds. II. Spectroscopic and environmental analysis of Thorne–Żytkow object and super-AGB star candidates","arxiv":1,"issue":"1","language":[{"iso":"eng"}],"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"publication_identifier":{"eissn":["1538-4357"],"issn":["0004-637X"]},"quality_controlled":"1","doi":"10.3847/1538-4357/aca655","year":"2023","_id":"13450","month":"01","oa_version":"Published Version","type":"journal_article","date_updated":"2023-08-21T12:07:05Z","abstract":[{"lang":"eng","text":"In previous work, we identified a population of 38 cool and luminous variable stars in the Magellanic Clouds and examined 11 in detail in order to classify them as either Thorne–Żytkow objects (TŻOs; red supergiants with a neutron star cores) or super-asymptotic giant branch (sAGB) stars (the most massive stars that will not undergo core collapse). This population includes HV 2112, a peculiar star previously considered in other works to be either a TŻO or high-mass asymptotic giant branch (AGB) star. Here we continue this investigation, using the kinematic and radio environments and local star formation history of these stars to place constraints on the age of the progenitor systems and the presence of past supernovae. These stars are not associated with regions of recent star formation, and we find no evidence of past supernovae at their locations. Finally, we also assess the presence of heavy elements and lithium in their spectra compared to red supergiants. We find strong absorption in Li and s-process elements compared to RSGs in most of the sample, consistent with sAGB nucleosynthesis, while HV 2112 shows additional strong lines associated with TŻO nucleosynthesis. Coupled with our previous mass estimates, the results are consistent with the stars being massive (∼4–6.5 M⊙) or sAGB (∼6.5–12 M⊙) stars in the thermally pulsing phase, providing crucial observations of the transition between low- and high-mass stellar populations. HV 2112 is more ambiguous; it could either be a maximally massive sAGB star, or a TŻO if the minimum mass for stability extends down to ≲13 M⊙."}],"date_created":"2023-08-03T10:10:12Z","volume":943,"external_id":{"arxiv":["2211.12438"]},"status":"public","citation":{"short":"A.J.G. O‘Grady, M.R. Drout, B.M. Gaensler, C.S. Kochanek, K.F. Neugent, C.L. Doherty, J.S. Speagle, B.J. Shappee, M. Rauch, Y.L.L. Götberg, B. Ludwig, T.A. Thompson, The Astrophysical Journal 943 (2023).","chicago":"O‘Grady, Anna J. G., Maria R. Drout, B. M. Gaensler, C. S. Kochanek, Kathryn F. Neugent, Carolyn L. Doherty, Joshua S. Speagle, et al. “Cool, Luminous, and Highly Variable Stars in the Magellanic Clouds. II. Spectroscopic and Environmental Analysis of Thorne–Żytkow Object and Super-AGB Star Candidates.” <i>The Astrophysical Journal</i>. American Astronomical Society, 2023. <a href=\"https://doi.org/10.3847/1538-4357/aca655\">https://doi.org/10.3847/1538-4357/aca655</a>.","ieee":"A. J. G. O‘Grady <i>et al.</i>, “Cool, luminous, and highly variable stars in the Magellanic Clouds. II. Spectroscopic and environmental analysis of Thorne–Żytkow object and super-AGB star candidates,” <i>The Astrophysical Journal</i>, vol. 943, no. 1. American Astronomical Society, 2023.","apa":"O‘Grady, A. J. G., Drout, M. R., Gaensler, B. M., Kochanek, C. S., Neugent, K. F., Doherty, C. L., … Thompson, T. A. (2023). Cool, luminous, and highly variable stars in the Magellanic Clouds. II. Spectroscopic and environmental analysis of Thorne–Żytkow object and super-AGB star candidates. <i>The Astrophysical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-4357/aca655\">https://doi.org/10.3847/1538-4357/aca655</a>","ista":"O‘Grady AJG, Drout MR, Gaensler BM, Kochanek CS, Neugent KF, Doherty CL, Speagle JS, Shappee BJ, Rauch M, Götberg YLL, Ludwig B, Thompson TA. 2023. Cool, luminous, and highly variable stars in the Magellanic Clouds. II. Spectroscopic and environmental analysis of Thorne–Żytkow object and super-AGB star candidates. The Astrophysical Journal. 943(1), 18.","mla":"O‘Grady, Anna J. G., et al. “Cool, Luminous, and Highly Variable Stars in the Magellanic Clouds. II. Spectroscopic and Environmental Analysis of Thorne–Żytkow Object and Super-AGB Star Candidates.” <i>The Astrophysical Journal</i>, vol. 943, no. 1, 18, American Astronomical Society, 2023, doi:<a href=\"https://doi.org/10.3847/1538-4357/aca655\">10.3847/1538-4357/aca655</a>.","ama":"O‘Grady AJG, Drout MR, Gaensler BM, et al. Cool, luminous, and highly variable stars in the Magellanic Clouds. II. Spectroscopic and environmental analysis of Thorne–Żytkow object and super-AGB star candidates. <i>The Astrophysical Journal</i>. 2023;943(1). doi:<a href=\"https://doi.org/10.3847/1538-4357/aca655\">10.3847/1538-4357/aca655</a>"},"intvolume":"       943","extern":"1","publication_status":"published","oa":1,"main_file_link":[{"open_access":"1","url":"https://doi.org/10.3847/1538-4357/aca655"}],"date_published":"2023-01-20T00:00:00Z"},{"publisher":"EDP Sciences","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_type":"original","article_processing_charge":"No","scopus_import":"1","publication":"Astronomy & Astrophysics","day":"01","author":[{"full_name":"Vink, Jorick S.","first_name":"Jorick S.","last_name":"Vink"},{"last_name":"Mehner","first_name":"A.","full_name":"Mehner, A."},{"first_name":"P. A.","last_name":"Crowther","full_name":"Crowther, P. A."},{"full_name":"Fullerton, A.","first_name":"A.","last_name":"Fullerton"},{"last_name":"Garcia","first_name":"M.","full_name":"Garcia, M."},{"full_name":"Martins, F.","last_name":"Martins","first_name":"F."},{"last_name":"Morrell","first_name":"N.","full_name":"Morrell, N."},{"last_name":"Oskinova","first_name":"L. M.","full_name":"Oskinova, L. M."},{"full_name":"St-Louis, N.","last_name":"St-Louis","first_name":"N."},{"full_name":"ud-Doula, A.","last_name":"ud-Doula","first_name":"A."},{"full_name":"Sander, A. A. C.","first_name":"A. A. C.","last_name":"Sander"},{"first_name":"H.","last_name":"Sana","full_name":"Sana, H."},{"full_name":"Bouret, J.-C.","last_name":"Bouret","first_name":"J.-C."},{"full_name":"Kubátová, B.","last_name":"Kubátová","first_name":"B."},{"last_name":"Marchant","first_name":"P.","full_name":"Marchant, P."},{"full_name":"Martins, L. P.","first_name":"L. P.","last_name":"Martins"},{"first_name":"A.","last_name":"Wofford","full_name":"Wofford, A."},{"first_name":"J. Th.","last_name":"van Loon","full_name":"van Loon, J. Th."},{"full_name":"Grace Telford, O.","last_name":"Grace Telford","first_name":"O."},{"orcid":"0000-0002-6960-6911","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","full_name":"Götberg, Ylva Louise Linsdotter","last_name":"Götberg","first_name":"Ylva Louise Linsdotter"},{"full_name":"Bowman, D. M.","first_name":"D. M.","last_name":"Bowman"},{"full_name":"Erba, C.","first_name":"C.","last_name":"Erba"},{"first_name":"V. M.","last_name":"Kalari","full_name":"Kalari, V. M."},{"full_name":"Abdul-Masih, M.","first_name":"M.","last_name":"Abdul-Masih"},{"full_name":"Alkousa, T.","last_name":"Alkousa","first_name":"T."},{"first_name":"F.","last_name":"Backs","full_name":"Backs, F."},{"last_name":"Barbosa","first_name":"C. L.","full_name":"Barbosa, C. L."},{"full_name":"Berlanas, S. R.","last_name":"Berlanas","first_name":"S. R."},{"full_name":"Bernini-Peron, M.","first_name":"M.","last_name":"Bernini-Peron"},{"full_name":"Bestenlehner, J. M.","first_name":"J. M.","last_name":"Bestenlehner"},{"first_name":"R.","last_name":"Blomme","full_name":"Blomme, R."},{"full_name":"Bodensteiner, J.","last_name":"Bodensteiner","first_name":"J."},{"last_name":"Brands","first_name":"S. A.","full_name":"Brands, S. A."},{"last_name":"Evans","first_name":"C. J.","full_name":"Evans, C. J."},{"first_name":"A.","last_name":"David-Uraz","full_name":"David-Uraz, A."},{"first_name":"F. A.","last_name":"Driessen","full_name":"Driessen, F. A."},{"first_name":"K.","last_name":"Dsilva","full_name":"Dsilva, K."},{"full_name":"Geen, S.","last_name":"Geen","first_name":"S."},{"full_name":"Gómez-González, V. M. A.","last_name":"Gómez-González","first_name":"V. M. A."},{"last_name":"Grassitelli","first_name":"L.","full_name":"Grassitelli, L."},{"last_name":"Hamann","first_name":"W.-R.","full_name":"Hamann, W.-R."},{"full_name":"Hawcroft, C.","last_name":"Hawcroft","first_name":"C."},{"first_name":"A.","last_name":"Herrero","full_name":"Herrero, A."},{"full_name":"Higgins, E. R.","last_name":"Higgins","first_name":"E. R."},{"first_name":"D.","last_name":"John Hillier","full_name":"John Hillier, D."},{"full_name":"Ignace, R.","first_name":"R.","last_name":"Ignace"},{"first_name":"A. G.","last_name":"Istrate","full_name":"Istrate, A. G."},{"full_name":"Kaper, L.","last_name":"Kaper","first_name":"L."},{"last_name":"Kee","first_name":"N. D.","full_name":"Kee, N. D."},{"first_name":"C.","last_name":"Kehrig","full_name":"Kehrig, C."},{"full_name":"Keszthelyi, Z.","last_name":"Keszthelyi","first_name":"Z."},{"full_name":"Klencki, J.","first_name":"J.","last_name":"Klencki"},{"full_name":"de Koter, A.","last_name":"de Koter","first_name":"A."},{"first_name":"R.","last_name":"Kuiper","full_name":"Kuiper, R."},{"full_name":"Laplace, E.","first_name":"E.","last_name":"Laplace"},{"last_name":"Larkin","first_name":"C. J. K.","full_name":"Larkin, C. J. K."},{"first_name":"R. R.","last_name":"Lefever","full_name":"Lefever, R. R."},{"last_name":"Leitherer","first_name":"C.","full_name":"Leitherer, C."},{"full_name":"Lennon, D. J.","first_name":"D. J.","last_name":"Lennon"},{"full_name":"Mahy, L.","first_name":"L.","last_name":"Mahy"},{"full_name":"Maíz Apellániz, J.","last_name":"Maíz Apellániz","first_name":"J."},{"full_name":"Maravelias, G.","last_name":"Maravelias","first_name":"G."},{"full_name":"Marcolino, W.","first_name":"W.","last_name":"Marcolino"},{"last_name":"McLeod","first_name":"A. F.","full_name":"McLeod, A. F."},{"full_name":"de Mink, S. E.","first_name":"S. E.","last_name":"de Mink"},{"last_name":"Najarro","first_name":"F.","full_name":"Najarro, F."},{"last_name":"Oey","first_name":"M. S.","full_name":"Oey, M. S."},{"last_name":"Parsons","first_name":"T. N.","full_name":"Parsons, T. N."},{"full_name":"Pauli, D.","last_name":"Pauli","first_name":"D."},{"full_name":"Pedersen, M. G.","last_name":"Pedersen","first_name":"M. G."},{"last_name":"Prinja","first_name":"R. K.","full_name":"Prinja, R. K."},{"last_name":"Ramachandran","first_name":"V.","full_name":"Ramachandran, V."},{"full_name":"Ramírez-Tannus, M. C.","first_name":"M. C.","last_name":"Ramírez-Tannus"},{"first_name":"G. N.","last_name":"Sabhahit","full_name":"Sabhahit, G. N."},{"last_name":"Schootemeijer","first_name":"A.","full_name":"Schootemeijer, A."},{"full_name":"Reyero Serantes, S.","last_name":"Reyero Serantes","first_name":"S."},{"full_name":"Shenar, T.","last_name":"Shenar","first_name":"T."},{"first_name":"G. S.","last_name":"Stringfellow","full_name":"Stringfellow, G. S."},{"first_name":"N.","last_name":"Sudnik","full_name":"Sudnik, N."},{"first_name":"F.","last_name":"Tramper","full_name":"Tramper, F."},{"full_name":"Wang, L.","last_name":"Wang","first_name":"L."}],"article_number":"A154","arxiv":1,"title":"X-shooting ULLYSES: Massive stars at low metallicity. I. Project description","language":[{"iso":"eng"}],"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"quality_controlled":"1","doi":"10.1051/0004-6361/202245650","year":"2023","_id":"14103","type":"journal_article","oa_version":"Published Version","month":"07","date_updated":"2023-08-22T11:01:07Z","abstract":[{"text":"Observations of individual massive stars, super-luminous supernovae, gamma-ray bursts, and gravitational wave events involving spectacular black hole mergers indicate that the low-metallicity Universe is fundamentally different from our own Galaxy. Many transient phenomena will remain enigmatic until we achieve a firm understanding of the physics and evolution of massive stars at low metallicity (Z). The Hubble Space Telescope has devoted 500 orbits to observing ∼250 massive stars at low Z in the ultraviolet (UV) with the COS and STIS spectrographs under the ULLYSES programme. The complementary X-Shooting ULLYSES (XShootU) project provides an enhanced legacy value with high-quality optical and near-infrared spectra obtained with the wide-wavelength coverage X-shooter spectrograph at ESO’s Very Large Telescope. We present an overview of the XShootU project, showing that combining ULLYSES UV and XShootU optical spectra is critical for the uniform determination of stellar parameters such as effective temperature, surface gravity, luminosity, and abundances, as well as wind properties such as mass-loss rates as a function of Z. As uncertainties in stellar and wind parameters percolate into many adjacent areas of astrophysics, the data and modelling of the XShootU project is expected to be a game changer for our physical understanding of massive stars at low Z. To be able to confidently interpret James Webb Space Telescope spectra of the first stellar generations, the individual spectra of low-Z stars need to be understood, which is exactly where XShootU can deliver.","lang":"eng"}],"date_created":"2023-08-21T10:12:35Z","volume":675,"external_id":{"arxiv":["2305.06376"]},"status":"public","citation":{"ama":"Vink JS, Mehner A, Crowther PA, et al. X-shooting ULLYSES: Massive stars at low metallicity. I. Project description. <i>Astronomy &#38; Astrophysics</i>. 2023;675. doi:<a href=\"https://doi.org/10.1051/0004-6361/202245650\">10.1051/0004-6361/202245650</a>","ista":"Vink JS, Mehner A, Crowther PA, Fullerton A, Garcia M, Martins F, Morrell N, Oskinova LM, St-Louis N, ud-Doula A, Sander AAC, Sana H, Bouret J-C, Kubátová B, Marchant P, Martins LP, Wofford A, van Loon JT, Grace Telford O, Götberg YLL, Bowman DM, Erba C, Kalari VM, Abdul-Masih M, Alkousa T, Backs F, Barbosa CL, Berlanas SR, Bernini-Peron M, Bestenlehner JM, Blomme R, Bodensteiner J, Brands SA, Evans CJ, David-Uraz A, Driessen FA, Dsilva K, Geen S, Gómez-González VMA, Grassitelli L, Hamann W-R, Hawcroft C, Herrero A, Higgins ER, John Hillier D, Ignace R, Istrate AG, Kaper L, Kee ND, Kehrig C, Keszthelyi Z, Klencki J, de Koter A, Kuiper R, Laplace E, Larkin CJK, Lefever RR, Leitherer C, Lennon DJ, Mahy L, Maíz Apellániz J, Maravelias G, Marcolino W, McLeod AF, de Mink SE, Najarro F, Oey MS, Parsons TN, Pauli D, Pedersen MG, Prinja RK, Ramachandran V, Ramírez-Tannus MC, Sabhahit GN, Schootemeijer A, Reyero Serantes S, Shenar T, Stringfellow GS, Sudnik N, Tramper F, Wang L. 2023. X-shooting ULLYSES: Massive stars at low metallicity. I. Project description. Astronomy &#38; Astrophysics. 675, A154.","mla":"Vink, Jorick S., et al. “X-Shooting ULLYSES: Massive Stars at Low Metallicity. I. Project Description.” <i>Astronomy &#38; Astrophysics</i>, vol. 675, A154, EDP Sciences, 2023, doi:<a href=\"https://doi.org/10.1051/0004-6361/202245650\">10.1051/0004-6361/202245650</a>.","apa":"Vink, J. S., Mehner, A., Crowther, P. A., Fullerton, A., Garcia, M., Martins, F., … Wang, L. (2023). X-shooting ULLYSES: Massive stars at low metallicity. I. Project description. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202245650\">https://doi.org/10.1051/0004-6361/202245650</a>","ieee":"J. S. Vink <i>et al.</i>, “X-shooting ULLYSES: Massive stars at low metallicity. I. Project description,” <i>Astronomy &#38; Astrophysics</i>, vol. 675. EDP Sciences, 2023.","chicago":"Vink, Jorick S., A. Mehner, P. A. Crowther, A. Fullerton, M. Garcia, F. Martins, N. Morrell, et al. “X-Shooting ULLYSES: Massive Stars at Low Metallicity. I. Project Description.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2023. <a href=\"https://doi.org/10.1051/0004-6361/202245650\">https://doi.org/10.1051/0004-6361/202245650</a>.","short":"J.S. Vink, A. Mehner, P.A. Crowther, A. Fullerton, M. Garcia, F. Martins, N. Morrell, L.M. Oskinova, N. St-Louis, A. ud-Doula, A.A.C. Sander, H. Sana, J.-C. Bouret, B. Kubátová, P. Marchant, L.P. Martins, A. Wofford, J.T. van Loon, O. Grace Telford, Y.L.L. Götberg, D.M. Bowman, C. Erba, V.M. Kalari, M. Abdul-Masih, T. Alkousa, F. Backs, C.L. Barbosa, S.R. Berlanas, M. Bernini-Peron, J.M. Bestenlehner, R. Blomme, J. Bodensteiner, S.A. Brands, C.J. Evans, A. David-Uraz, F.A. Driessen, K. Dsilva, S. Geen, V.M.A. Gómez-González, L. Grassitelli, W.-R. Hamann, C. Hawcroft, A. Herrero, E.R. Higgins, D. John Hillier, R. Ignace, A.G. Istrate, L. Kaper, N.D. Kee, C. Kehrig, Z. Keszthelyi, J. Klencki, A. de Koter, R. Kuiper, E. Laplace, C.J.K. Larkin, R.R. Lefever, C. Leitherer, D.J. Lennon, L. Mahy, J. Maíz Apellániz, G. Maravelias, W. Marcolino, A.F. McLeod, S.E. de Mink, F. Najarro, M.S. Oey, T.N. Parsons, D. Pauli, M.G. Pedersen, R.K. Prinja, V. Ramachandran, M.C. Ramírez-Tannus, G.N. Sabhahit, A. Schootemeijer, S. Reyero Serantes, T. Shenar, G.S. Stringfellow, N. Sudnik, F. Tramper, L. Wang, Astronomy &#38; Astrophysics 675 (2023)."},"intvolume":"       675","extern":"1","publication_status":"published","oa":1,"main_file_link":[{"url":"https://doi.org/10.1051/0004-6361/202245650","open_access":"1"}],"date_published":"2023-07-01T00:00:00Z"},{"citation":{"mla":"Farmer, R., et al. “Observational Predictions for Thorne–Żytkow Objects.” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 524, no. 2, Oxford University Press, 2023, pp. 1692–709, doi:<a href=\"https://doi.org/10.1093/mnras/stad1977\">10.1093/mnras/stad1977</a>.","ista":"Farmer R, Renzo M, Götberg YLL, Bellinger E, Justham S, de Mink SE. 2023. Observational predictions for Thorne–Żytkow objects. Monthly Notices of the Royal Astronomical Society. 524(2), 1692–1709.","apa":"Farmer, R., Renzo, M., Götberg, Y. L. L., Bellinger, E., Justham, S., &#38; de Mink, S. E. (2023). Observational predictions for Thorne–Żytkow objects. <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/mnras/stad1977\">https://doi.org/10.1093/mnras/stad1977</a>","ama":"Farmer R, Renzo M, Götberg YLL, Bellinger E, Justham S, de Mink SE. Observational predictions for Thorne–Żytkow objects. <i>Monthly Notices of the Royal Astronomical Society</i>. 2023;524(2):1692-1709. doi:<a href=\"https://doi.org/10.1093/mnras/stad1977\">10.1093/mnras/stad1977</a>","short":"R. Farmer, M. Renzo, Y.L.L. Götberg, E. Bellinger, S. Justham, S.E. de Mink, Monthly Notices of the Royal Astronomical Society 524 (2023) 1692–1709.","ieee":"R. Farmer, M. Renzo, Y. L. L. Götberg, E. Bellinger, S. Justham, and S. E. de Mink, “Observational predictions for Thorne–Żytkow objects,” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 524, no. 2. Oxford University Press, pp. 1692–1709, 2023.","chicago":"Farmer, R, M Renzo, Ylva Louise Linsdotter Götberg, E Bellinger, S Justham, and S E de Mink. “Observational Predictions for Thorne–Żytkow Objects.” <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press, 2023. <a href=\"https://doi.org/10.1093/mnras/stad1977\">https://doi.org/10.1093/mnras/stad1977</a>."},"extern":"1","intvolume":"       524","external_id":{"arxiv":["2305.07337"]},"status":"public","main_file_link":[{"url":"https://arxiv.org/abs/2305.07337","open_access":"1"}],"date_published":"2023-09-01T00:00:00Z","oa":1,"publication_status":"published","_id":"14104","year":"2023","date_created":"2023-08-21T10:13:56Z","volume":524,"month":"09","type":"journal_article","oa_version":"Preprint","date_updated":"2023-08-21T12:12:48Z","abstract":[{"text":"Thorne–Żytkow objects (TŻO) are potential end products of the merger of a neutron star with a non-degenerate star. In this work, we have computed the first grid of evolutionary models of TŻOs with the MESA stellar evolution code. With these models, we predict several observational properties of TŻOs, including their surface temperatures and luminosities, pulsation periods, and nucleosynthetic products. We expand the range of possible TŻO solutions to cover 3.45≲log(Teff/K)≲3.65 and 4.85≲log(L/L⊙)≲5.5⁠. Due to the much higher densities our TŻOs reach compared to previous models, if TŻOs form we expect them to be stable over a larger mass range than previously predicted, without exhibiting a gap in their mass distribution. Using the GYRE stellar pulsation code we show that TŻOs should have fundamental pulsation periods of 1000–2000 d, and period ratios of ≈0.2–0.3. Models computed with a large 399 isotope fully coupled nuclear network show a nucleosynthetic signal that is different to previously predicted. We propose a new nucleosynthetic signal to determine a star’s status as a TŻO: the isotopologues 44TiO2 and 44TiO⁠, which will have a shift in their spectral features as compared to stable titanium-containing molecules. We find that in the local Universe (∼SMC metallicities and above) TŻOs show little heavy metal enrichment, potentially explaining the difficulty in finding TŻOs to-date.","lang":"eng"}],"page":"1692-1709","issue":"2","language":[{"iso":"eng"}],"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"quality_controlled":"1","doi":"10.1093/mnras/stad1977","publication_identifier":{"issn":["0035-8711"],"eissn":["1365-2966"]},"article_type":"original","article_processing_charge":"No","scopus_import":"1","publication":"Monthly Notices of the Royal Astronomical Society","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publisher":"Oxford University Press","title":"Observational predictions for Thorne–Żytkow objects","arxiv":1,"day":"01","author":[{"full_name":"Farmer, R","first_name":"R","last_name":"Farmer"},{"last_name":"Renzo","first_name":"M","full_name":"Renzo, M"},{"first_name":"Ylva Louise Linsdotter","last_name":"Götberg","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911","full_name":"Götberg, Ylva Louise Linsdotter"},{"full_name":"Bellinger, E","last_name":"Bellinger","first_name":"E"},{"full_name":"Justham, S","first_name":"S","last_name":"Justham"},{"full_name":"de Mink, S E","last_name":"de Mink","first_name":"S E"}]},{"publication_identifier":{"eissn":["1538-4357"],"issn":["0004-637X"]},"doi":"10.3847/1538-4357/aca295","quality_controlled":"1","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"language":[{"iso":"eng"}],"issue":"2","author":[{"full_name":"Gull, Maude","first_name":"Maude","last_name":"Gull"},{"last_name":"Weisz","first_name":"Daniel R.","full_name":"Weisz, Daniel R."},{"full_name":"Senchyna, Peter","last_name":"Senchyna","first_name":"Peter"},{"full_name":"Sandford, Nathan R.","last_name":"Sandford","first_name":"Nathan R."},{"full_name":"Choi, Yumi","first_name":"Yumi","last_name":"Choi"},{"full_name":"McLeod, Anna F.","last_name":"McLeod","first_name":"Anna F."},{"last_name":"El-Badry","first_name":"Kareem","full_name":"El-Badry, Kareem"},{"full_name":"Götberg, Ylva Louise Linsdotter","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911","first_name":"Ylva Louise Linsdotter","last_name":"Götberg"},{"full_name":"Gilbert, Karoline M.","last_name":"Gilbert","first_name":"Karoline M."},{"first_name":"Martha","last_name":"Boyer","full_name":"Boyer, Martha"},{"full_name":"Dalcanton, Julianne J.","first_name":"Julianne J.","last_name":"Dalcanton"},{"full_name":"GuhaThakurta, Puragra","first_name":"Puragra","last_name":"GuhaThakurta"},{"first_name":"Steven","last_name":"Goldman","full_name":"Goldman, Steven"},{"last_name":"Marigo","first_name":"Paola","full_name":"Marigo, Paola"},{"full_name":"McQuinn, Kristen B. W.","first_name":"Kristen B. W.","last_name":"McQuinn"},{"full_name":"Pastorelli, Giada","last_name":"Pastorelli","first_name":"Giada"},{"last_name":"Stark","first_name":"Daniel P.","full_name":"Stark, Daniel P."},{"full_name":"Skillman, Evan","last_name":"Skillman","first_name":"Evan"},{"last_name":"Ting","first_name":"Yuan-sen","full_name":"Ting, Yuan-sen"},{"full_name":"Williams, Benjamin F.","last_name":"Williams","first_name":"Benjamin F."}],"day":"27","arxiv":1,"title":"A panchromatic study of massive stars in the extremely metal-poor local group dwarf galaxy Leo A","article_number":"206","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publisher":"American Astronomical Society","publication":"The Astrophysical Journal","scopus_import":"1","article_processing_charge":"No","article_type":"original","oa":1,"publication_status":"published","date_published":"2022-12-27T00:00:00Z","main_file_link":[{"url":"https://doi.org/10.3847/1538-4357/aca295","open_access":"1"}],"external_id":{"arxiv":["2211.14349"]},"status":"public","intvolume":"       941","extern":"1","citation":{"ista":"Gull M, Weisz DR, Senchyna P, Sandford NR, Choi Y, McLeod AF, El-Badry K, Götberg YLL, Gilbert KM, Boyer M, Dalcanton JJ, GuhaThakurta P, Goldman S, Marigo P, McQuinn KBW, Pastorelli G, Stark DP, Skillman E, Ting Y, Williams BF. 2022. A panchromatic study of massive stars in the extremely metal-poor local group dwarf galaxy Leo A. The Astrophysical Journal. 941(2), 206.","mla":"Gull, Maude, et al. “A Panchromatic Study of Massive Stars in the Extremely Metal-Poor Local Group Dwarf Galaxy Leo A.” <i>The Astrophysical Journal</i>, vol. 941, no. 2, 206, American Astronomical Society, 2022, doi:<a href=\"https://doi.org/10.3847/1538-4357/aca295\">10.3847/1538-4357/aca295</a>.","apa":"Gull, M., Weisz, D. R., Senchyna, P., Sandford, N. R., Choi, Y., McLeod, A. F., … Williams, B. F. (2022). A panchromatic study of massive stars in the extremely metal-poor local group dwarf galaxy Leo A. <i>The Astrophysical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-4357/aca295\">https://doi.org/10.3847/1538-4357/aca295</a>","ama":"Gull M, Weisz DR, Senchyna P, et al. A panchromatic study of massive stars in the extremely metal-poor local group dwarf galaxy Leo A. <i>The Astrophysical Journal</i>. 2022;941(2). doi:<a href=\"https://doi.org/10.3847/1538-4357/aca295\">10.3847/1538-4357/aca295</a>","short":"M. Gull, D.R. Weisz, P. Senchyna, N.R. Sandford, Y. Choi, A.F. McLeod, K. El-Badry, Y.L.L. Götberg, K.M. Gilbert, M. Boyer, J.J. Dalcanton, P. GuhaThakurta, S. Goldman, P. Marigo, K.B.W. McQuinn, G. Pastorelli, D.P. Stark, E. Skillman, Y. Ting, B.F. Williams, The Astrophysical Journal 941 (2022).","ieee":"M. Gull <i>et al.</i>, “A panchromatic study of massive stars in the extremely metal-poor local group dwarf galaxy Leo A,” <i>The Astrophysical Journal</i>, vol. 941, no. 2. American Astronomical Society, 2022.","chicago":"Gull, Maude, Daniel R. Weisz, Peter Senchyna, Nathan R. Sandford, Yumi Choi, Anna F. McLeod, Kareem El-Badry, et al. “A Panchromatic Study of Massive Stars in the Extremely Metal-Poor Local Group Dwarf Galaxy Leo A.” <i>The Astrophysical Journal</i>. American Astronomical Society, 2022. <a href=\"https://doi.org/10.3847/1538-4357/aca295\">https://doi.org/10.3847/1538-4357/aca295</a>."},"date_updated":"2023-08-21T12:04:58Z","abstract":[{"lang":"eng","text":"We characterize massive stars (M > 8 M⊙) in the nearby (D ∼ 0.8 Mpc) extremely metal-poor (Z ∼ 5% Z⊙) galaxy Leo A using Hubble Space Telescope ultraviolet (UV), optical, and near-infrared (NIR) imaging along with Keck/Low-Resolution Imaging Spectrograph and MMT/Binospec optical spectroscopy for 18 main-sequence OB stars. We find that: (a) 12 of our 18 stars show emission lines, despite not being associated with an H ii region, suggestive of stellar activity (e.g., mass loss, accretion, binary star interaction), which is consistent with previous predictions of enhanced activity at low metallicity; (b) six are Be stars, which are the first to be spectroscopically studied at such low metallicity—these Be stars have unusual panchromatic SEDs; (c) for stars well fit by the TLUSTY nonlocal thermodynamic equilibrium models, the photometric and spectroscopic values of $\\mathrm{log}({T}_{\\mathrm{eff}})$ and $\\mathrm{log}(g)$ agree to within ∼0.01 dex and ∼0.18 dex, respectively, indicating that near-UV/optical/NIR imaging can be used to reliably characterize massive (M ∼ 8–30 M⊙) main-sequence star properties relative to optical spectroscopy; (d) the properties of the most-massive stars in H II regions are consistent with constraints from previous nebular emission line studies; and (e) 13 stars with M > 8M⊙ are >40 pc from a known star cluster or H II region. Our sample comprises ∼50% of all known massive stars at Z ≲ 10% Z⊙with derived stellar parameters, high-quality optical spectra, and panchromatic photometry."}],"type":"journal_article","month":"12","oa_version":"Published Version","volume":941,"date_created":"2023-08-03T10:10:25Z","year":"2022","_id":"13451"},{"citation":{"ama":"Keszthelyi Z, de Koter A, Götberg YLL, et al. The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at Solar, LMC, and SMC metallicities. <i>Monthly Notices of the Royal Astronomical Society</i>. 2022;517(2):2028-2055. doi:<a href=\"https://doi.org/10.1093/mnras/stac2598\">10.1093/mnras/stac2598</a>","apa":"Keszthelyi, Z., de Koter, A., Götberg, Y. L. L., Meynet, G., Brands, S. A., Petit, V., … ud-Doula, A. (2022). The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at Solar, LMC, and SMC metallicities. <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/mnras/stac2598\">https://doi.org/10.1093/mnras/stac2598</a>","ista":"Keszthelyi Z, de Koter A, Götberg YLL, Meynet G, Brands SA, Petit V, Carrington M, David-Uraz A, Geen ST, Georgy C, Hirschi R, Puls J, Ramalatswa KJ, Shultz ME, ud-Doula A. 2022. The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at Solar, LMC, and SMC metallicities. Monthly Notices of the Royal Astronomical Society. 517(2), 2028–2055.","mla":"Keszthelyi, Z., et al. “The Effects of Surface Fossil Magnetic Fields on Massive Star Evolution: IV. Grids of Models at Solar, LMC, and SMC Metallicities.” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 517, no. 2, Oxford University Press, 2022, pp. 2028–55, doi:<a href=\"https://doi.org/10.1093/mnras/stac2598\">10.1093/mnras/stac2598</a>.","chicago":"Keszthelyi, Z, A de Koter, Ylva Louise Linsdotter Götberg, G Meynet, S A Brands, V Petit, M Carrington, et al. “The Effects of Surface Fossil Magnetic Fields on Massive Star Evolution: IV. Grids of Models at Solar, LMC, and SMC Metallicities.” <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press, 2022. <a href=\"https://doi.org/10.1093/mnras/stac2598\">https://doi.org/10.1093/mnras/stac2598</a>.","ieee":"Z. Keszthelyi <i>et al.</i>, “The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at Solar, LMC, and SMC metallicities,” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 517, no. 2. Oxford University Press, pp. 2028–2055, 2022.","short":"Z. Keszthelyi, A. de Koter, Y.L.L. Götberg, G. Meynet, S.A. Brands, V. Petit, M. Carrington, A. David-Uraz, S.T. Geen, C. Georgy, R. Hirschi, J. Puls, K.J. Ramalatswa, M.E. Shultz, A. ud-Doula, Monthly Notices of the Royal Astronomical Society 517 (2022) 2028–2055."},"intvolume":"       517","extern":"1","external_id":{"arxiv":["2209.06350"]},"status":"public","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2209.06350"}],"date_published":"2022-12-01T00:00:00Z","publication_status":"published","oa":1,"_id":"13452","year":"2022","date_created":"2023-08-03T10:10:37Z","volume":517,"month":"12","type":"journal_article","oa_version":"Preprint","abstract":[{"lang":"eng","text":"Magnetic fields can drastically change predictions of evolutionary models of massive stars via mass-loss quenching, magnetic braking, and efficient angular momentum transport, which we aim to quantify in this work. We use the MESA software instrument to compute an extensive main-sequence grid of stellar structure and evolution models, as well as isochrones, accounting for the effects attributed to a surface fossil magnetic field. The grid is densely populated in initial mass (3–60 M⊙), surface equatorial magnetic field strength (0–50 kG), and metallicity (representative of the Solar neighbourhood and the Magellanic Clouds). We use two magnetic braking and two chemical mixing schemes and compare the model predictions for slowly rotating, nitrogen-enriched (‘Group 2’) stars with observations in the Large Magellanic Cloud. We quantify a range of initial field strengths that allow for producing Group 2 stars and find that typical values (up to a few kG) lead to solutions. Between the subgrids, we find notable departures in surface abundances and evolutionary paths. In our magnetic models, chemical mixing is always less efficient compared to non-magnetic models due to the rapid spin-down. We identify that quasi-chemically homogeneous main sequence evolution by efficient mixing could be prevented by fossil magnetic fields. We recommend comparing this grid of evolutionary models with spectropolarimetric and spectroscopic observations with the goals of (i) revisiting the derived stellar parameters of known magnetic stars, and (ii) observationally constraining the uncertain magnetic braking and chemical mixing schemes."}],"date_updated":"2023-08-21T12:02:17Z","page":"2028-2055","issue":"2","language":[{"iso":"eng"}],"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"quality_controlled":"1","doi":"10.1093/mnras/stac2598","publication_identifier":{"issn":["0035-8711"],"eissn":["1365-2966"]},"article_type":"original","scopus_import":"1","article_processing_charge":"No","publication":"Monthly Notices of the Royal Astronomical Society","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publisher":"Oxford University Press","title":"The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at Solar, LMC, and SMC metallicities","arxiv":1,"day":"01","author":[{"full_name":"Keszthelyi, Z","first_name":"Z","last_name":"Keszthelyi"},{"full_name":"de Koter, A","first_name":"A","last_name":"de Koter"},{"first_name":"Ylva Louise Linsdotter","last_name":"Götberg","orcid":"0000-0002-6960-6911","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","full_name":"Götberg, Ylva Louise Linsdotter"},{"last_name":"Meynet","first_name":"G","full_name":"Meynet, G"},{"last_name":"Brands","first_name":"S A","full_name":"Brands, S A"},{"last_name":"Petit","first_name":"V","full_name":"Petit, V"},{"full_name":"Carrington, M","last_name":"Carrington","first_name":"M"},{"last_name":"David-Uraz","first_name":"A","full_name":"David-Uraz, A"},{"last_name":"Geen","first_name":"S T","full_name":"Geen, S T"},{"first_name":"C","last_name":"Georgy","full_name":"Georgy, C"},{"last_name":"Hirschi","first_name":"R","full_name":"Hirschi, R"},{"full_name":"Puls, J","last_name":"Puls","first_name":"J"},{"first_name":"K J","last_name":"Ramalatswa","full_name":"Ramalatswa, K J"},{"full_name":"Shultz, M E","first_name":"M E","last_name":"Shultz"},{"first_name":"A","last_name":"ud-Doula","full_name":"ud-Doula, A"}]},{"day":"01","author":[{"full_name":"Keszthelyi, Z.","first_name":"Z.","last_name":"Keszthelyi"},{"full_name":"Koter, A. de","last_name":"Koter","first_name":"A. de"},{"orcid":"0000-0002-6960-6911","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","full_name":"Götberg, Ylva Louise Linsdotter","last_name":"Götberg","first_name":"Ylva Louise Linsdotter"},{"first_name":"G.","last_name":"Meynet","full_name":"Meynet, G."},{"last_name":"Brands","first_name":"S. A.","full_name":"Brands, S. A."},{"full_name":"Petit, V.","first_name":"V.","last_name":"Petit"},{"first_name":"M.","last_name":"Carrington","full_name":"Carrington, M."},{"full_name":"A. David-Uraz, A. David-Uraz","last_name":"A. David-Uraz","first_name":"A. David-Uraz"},{"full_name":"Geen, S. T.","first_name":"S. T.","last_name":"Geen"},{"last_name":"Georgy","first_name":"C.","full_name":"Georgy, C."},{"last_name":"Hirschi","first_name":"R.","full_name":"Hirschi, R."},{"full_name":"Puls, J.","last_name":"Puls","first_name":"J."},{"first_name":"K. J.","last_name":"Ramalatswa","full_name":"Ramalatswa, K. J."},{"last_name":"Shultz","first_name":"M. E.","full_name":"Shultz, M. E."},{"first_name":"A. ud-Doula","last_name":"A. ud-Doula","full_name":"A. ud-Doula, A. ud-Doula"}],"arxiv":1,"title":"The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at solar, LMC, and SMC metallicities","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publisher":"Oxford Academic","article_processing_charge":"No","scopus_import":"1","article_type":"original","publication":"Monthly Notices of the Royal Astronomical Society","publication_identifier":{"eissn":["1365-2966"],"issn":["0035-8711"]},"quality_controlled":"1","doi":"10.1093/mnras/stac2598","language":[{"iso":"eng"}],"issue":"2","abstract":[{"text":"Magnetic fields can drastically change predictions of evolutionary models of massive stars via mass-loss quenching, magnetic braking, and efficient angular momentum transport, which we aim to quantify in this work. We use the MESA software instrument to compute an extensive main-sequence grid of stellar structure and evolution models, as well as isochrones, accounting for the effects attributed to a surface fossil magnetic field. The grid is densely populated in initial mass (3–60 M⊙), surface equatorial magnetic field strength (0–50 kG), and metallicity (representative of the Solar neighbourhood and the Magellanic Clouds). We use two magnetic braking and two chemical mixing schemes and compare the model predictions for slowly rotating, nitrogen-enriched (‘Group 2’) stars with observations in the Large Magellanic Cloud. We quantify a range of initial field strengths that allow for producing Group 2 stars and find that typical values (up to a few kG) lead to solutions. Between the subgrids, we find notable departures in surface abundances and evolutionary paths. In our magnetic models, chemical mixing is always less efficient compared to non-magnetic models due to the rapid spin-down. We identify that quasi-chemically homogeneous main sequence evolution by efficient mixing could be prevented by fossil magnetic fields. We recommend comparing this grid of evolutionary models with spectropolarimetric and spectroscopic observations with the goals of (i) revisiting the derived stellar parameters of known magnetic stars, and (ii) observationally constraining the uncertain magnetic braking and chemical mixing schemes.","lang":"eng"}],"date_updated":"2023-08-22T13:18:34Z","oa_version":"Published Version","month":"12","type":"journal_article","page":"2028-2055","date_created":"2023-08-21T10:11:21Z","volume":517,"year":"2022","_id":"14098","oa":1,"publication_status":"published","main_file_link":[{"url":"https://doi.org/10.1093/mnras/stac2598","open_access":"1"}],"date_published":"2022-12-01T00:00:00Z","status":"public","external_id":{"arxiv":["2209.06350"]},"citation":{"apa":"Keszthelyi, Z., Koter, A. de, Götberg, Y. L. L., Meynet, G., Brands, S. A., Petit, V., … A. ud-Doula, A. ud-Doula. (2022). The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at solar, LMC, and SMC metallicities. <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford Academic. <a href=\"https://doi.org/10.1093/mnras/stac2598\">https://doi.org/10.1093/mnras/stac2598</a>","mla":"Keszthelyi, Z., et al. “The Effects of Surface Fossil Magnetic Fields on Massive Star Evolution: IV. Grids of Models at Solar, LMC, and SMC Metallicities.” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 517, no. 2, Oxford Academic, 2022, pp. 2028–55, doi:<a href=\"https://doi.org/10.1093/mnras/stac2598\">10.1093/mnras/stac2598</a>.","ista":"Keszthelyi Z, Koter A de, Götberg YLL, Meynet G, Brands SA, Petit V, Carrington M, A. David-Uraz AD-U, Geen ST, Georgy C, Hirschi R, Puls J, Ramalatswa KJ, Shultz ME, A. ud-Doula A ud-Doula. 2022. The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at solar, LMC, and SMC metallicities. Monthly Notices of the Royal Astronomical Society. 517(2), 2028–2055.","ama":"Keszthelyi Z, Koter A de, Götberg YLL, et al. The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at solar, LMC, and SMC metallicities. <i>Monthly Notices of the Royal Astronomical Society</i>. 2022;517(2):2028-2055. doi:<a href=\"https://doi.org/10.1093/mnras/stac2598\">10.1093/mnras/stac2598</a>","short":"Z. Keszthelyi, A. de Koter, Y.L.L. Götberg, G. Meynet, S.A. Brands, V. Petit, M. Carrington, A.D.-U. A. David-Uraz, S.T. Geen, C. Georgy, R. Hirschi, J. Puls, K.J. Ramalatswa, M.E. Shultz, A. ud-Doula A. ud-Doula, Monthly Notices of the Royal Astronomical Society 517 (2022) 2028–2055.","chicago":"Keszthelyi, Z., A. de Koter, Ylva Louise Linsdotter Götberg, G. Meynet, S. A. Brands, V. Petit, M. Carrington, et al. “The Effects of Surface Fossil Magnetic Fields on Massive Star Evolution: IV. Grids of Models at Solar, LMC, and SMC Metallicities.” <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford Academic, 2022. <a href=\"https://doi.org/10.1093/mnras/stac2598\">https://doi.org/10.1093/mnras/stac2598</a>.","ieee":"Z. Keszthelyi <i>et al.</i>, “The effects of surface fossil magnetic fields on massive star evolution: IV. Grids of models at solar, LMC, and SMC metallicities,” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 517, no. 2. Oxford Academic, pp. 2028–2055, 2022."},"extern":"1","intvolume":"       517"},{"doi":"10.48550/arXiv.2211.07060","date_published":"2022-11-14T00:00:00Z","main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2211.07060","open_access":"1"}],"oa":1,"publication_status":"submitted","extern":"1","language":[{"iso":"eng"}],"citation":{"mla":"Keszthelyi, Z., et al. “Spin-down and Reduced Mass Loss in Early-Type Stars with Large-Scale Magnetic Fields.” <i>ArXiv</i>, 2211.07060, doi:<a href=\"https://doi.org/10.48550/arXiv.2211.07060\">10.48550/arXiv.2211.07060</a>.","ista":"Keszthelyi Z, Koter A de, Götberg YLL, Meynet G, Brands SA, Petit V, Carrington M, A. David-Uraz AD-U, Geen ST, Georgy C, Hirschi R, Puls J, Ramalatswa KJ, Shultz ME, A. ud-Doula A ud-Doula. Spin-down and reduced mass loss in early-type stars with large-scale magnetic fields. arXiv, 2211.07060.","apa":"Keszthelyi, Z., Koter, A. de, Götberg, Y. L. L., Meynet, G., Brands, S. A., Petit, V., … A. ud-Doula, A. ud-Doula. (n.d.). Spin-down and reduced mass loss in early-type stars with large-scale magnetic fields. <i>arXiv</i>. <a href=\"https://doi.org/10.48550/arXiv.2211.07060\">https://doi.org/10.48550/arXiv.2211.07060</a>","ama":"Keszthelyi Z, Koter A de, Götberg YLL, et al. Spin-down and reduced mass loss in early-type stars with large-scale magnetic fields. <i>arXiv</i>. doi:<a href=\"https://doi.org/10.48550/arXiv.2211.07060\">10.48550/arXiv.2211.07060</a>","short":"Z. Keszthelyi, A. de Koter, Y.L.L. Götberg, G. Meynet, S.A. Brands, V. Petit, M. Carrington, A.D.-U. A. David-Uraz, S.T. Geen, C. Georgy, R. Hirschi, J. Puls, K.J. Ramalatswa, M.E. Shultz, A. ud-Doula A. ud-Doula, ArXiv (n.d.).","ieee":"Z. Keszthelyi <i>et al.</i>, “Spin-down and reduced mass loss in early-type stars with large-scale magnetic fields,” <i>arXiv</i>. .","chicago":"Keszthelyi, Z., A. de Koter, Ylva Louise Linsdotter Götberg, G. Meynet, S. A. Brands, V. Petit, M. Carrington, et al. “Spin-down and Reduced Mass Loss in Early-Type Stars with Large-Scale Magnetic Fields.” <i>ArXiv</i>, n.d. <a href=\"https://doi.org/10.48550/arXiv.2211.07060\">https://doi.org/10.48550/arXiv.2211.07060</a>."},"external_id":{"arxiv":["2211.07060"]},"status":"public","article_number":"2211.07060","title":"Spin-down and reduced mass loss in early-type stars with large-scale magnetic fields","arxiv":1,"date_created":"2023-08-21T10:11:37Z","author":[{"first_name":"Z.","last_name":"Keszthelyi","full_name":"Keszthelyi, Z."},{"full_name":"Koter, A. de","last_name":"Koter","first_name":"A. de"},{"full_name":"Götberg, Ylva Louise Linsdotter","orcid":"0000-0002-6960-6911","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","last_name":"Götberg","first_name":"Ylva Louise Linsdotter"},{"first_name":"G.","last_name":"Meynet","full_name":"Meynet, G."},{"full_name":"Brands, S. A.","first_name":"S. A.","last_name":"Brands"},{"full_name":"Petit, V.","last_name":"Petit","first_name":"V."},{"full_name":"Carrington, M.","first_name":"M.","last_name":"Carrington"},{"last_name":"A. David-Uraz","first_name":"A. David-Uraz","full_name":"A. David-Uraz, A. David-Uraz"},{"last_name":"Geen","first_name":"S. T.","full_name":"Geen, S. T."},{"full_name":"Georgy, C.","last_name":"Georgy","first_name":"C."},{"full_name":"Hirschi, R.","first_name":"R.","last_name":"Hirschi"},{"full_name":"Puls, J.","first_name":"J.","last_name":"Puls"},{"last_name":"Ramalatswa","first_name":"K. J.","full_name":"Ramalatswa, K. J."},{"full_name":"Shultz, M. E.","last_name":"Shultz","first_name":"M. E."},{"last_name":"A. ud-Doula","first_name":"A. ud-Doula","full_name":"A. ud-Doula, A. ud-Doula"}],"oa_version":"Submitted Version","type":"preprint","month":"11","abstract":[{"lang":"eng","text":"Magnetism can greatly impact the evolution of stars. In some stars with OBA spectral types there is direct evidence via the Zeeman effect for stable, large-scale magnetospheres, which lead to the spin-down of the stellar surface and reduced mass loss. So far, a comprehensive grid of stellar structure and evolution models accounting for these effects was lacking. For this reason, we computed and studied models with two magnetic braking and two chemical mixing schemes in three metallicity environments with the MESA software instrument. We find notable differences between the subgrids, which affects the model predictions and thus the detailed characterisation of stars. We are able to quantify the impact of magnetic fields in terms of preventing quasi-chemically homogeneous evolution and producing slowly-rotating, nitrogen-enriched (\"Group 2\") stars. Our model grid is fully open access and open source."}],"date_updated":"2023-08-22T13:20:15Z","day":"14","_id":"14099","publication":"arXiv","article_processing_charge":"No","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","year":"2022"},{"publication_status":"published","oa":1,"main_file_link":[{"url":"https://arxiv.org/abs/2107.10933","open_access":"1"}],"date_published":"2021-12-29T00:00:00Z","external_id":{"arxiv":["2107.10933"]},"status":"public","citation":{"ista":"Renzo M, Götberg YLL. 2021. Evolution of accretor stars in massive binaries: Broader implications from modeling ζ Ophiuchi. The Astrophysical Journal. 923(2), 277.","mla":"Renzo, M., and Ylva Louise Linsdotter Götberg. “Evolution of Accretor Stars in Massive Binaries: Broader Implications from Modeling ζ Ophiuchi.” <i>The Astrophysical Journal</i>, vol. 923, no. 2, 277, American Astronomical Society, 2021, doi:<a href=\"https://doi.org/10.3847/1538-4357/ac29c5\">10.3847/1538-4357/ac29c5</a>.","apa":"Renzo, M., &#38; Götberg, Y. L. L. (2021). Evolution of accretor stars in massive binaries: Broader implications from modeling ζ Ophiuchi. <i>The Astrophysical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-4357/ac29c5\">https://doi.org/10.3847/1538-4357/ac29c5</a>","ama":"Renzo M, Götberg YLL. Evolution of accretor stars in massive binaries: Broader implications from modeling ζ Ophiuchi. <i>The Astrophysical Journal</i>. 2021;923(2). doi:<a href=\"https://doi.org/10.3847/1538-4357/ac29c5\">10.3847/1538-4357/ac29c5</a>","short":"M. Renzo, Y.L.L. Götberg, The Astrophysical Journal 923 (2021).","ieee":"M. Renzo and Y. L. L. Götberg, “Evolution of accretor stars in massive binaries: Broader implications from modeling ζ Ophiuchi,” <i>The Astrophysical Journal</i>, vol. 923, no. 2. American Astronomical Society, 2021.","chicago":"Renzo, M., and Ylva Louise Linsdotter Götberg. “Evolution of Accretor Stars in Massive Binaries: Broader Implications from Modeling ζ Ophiuchi.” <i>The Astrophysical Journal</i>. American Astronomical Society, 2021. <a href=\"https://doi.org/10.3847/1538-4357/ac29c5\">https://doi.org/10.3847/1538-4357/ac29c5</a>."},"intvolume":"       923","extern":"1","month":"12","type":"journal_article","oa_version":"Preprint","abstract":[{"lang":"eng","text":"Most massive stars are born in binaries close enough for mass transfer episodes. These modify the appearance, structure, and future evolution of both stars. We compute the evolution of a 100-day-period binary, consisting initially of a 25 M⊙ star and a 17 M⊙ star, which experiences stable mass transfer. We focus on the impact of mass accretion on the surface composition, internal rotation, and structure of the accretor. To anchor our models, we show that our accretor broadly reproduces the properties of ζ Ophiuchi, which has long been proposed to have accreted mass before being ejected as a runaway star when the companion exploded. We compare our accretor to models of single rotating stars and find that the later and stronger spin-up provided by mass accretion produces significant differences. Specifically, the core of the accretor retains higher spin at the end of the main sequence, and a convective layer develops that changes its density profile. Moreover, the surface of the accretor star is polluted by CNO-processed material donated by the companion. Our models show effects of mass accretion in binaries that are not captured in single rotating stellar models. This possibly impacts the further evolution (either in a binary or as single stars), the final collapse, and the resulting spin of the compact object."}],"date_updated":"2023-08-21T11:59:34Z","date_created":"2023-08-03T10:10:48Z","volume":923,"year":"2021","_id":"13453","publication_identifier":{"eissn":["1538-4357"],"issn":["0004-637X"]},"quality_controlled":"1","doi":"10.3847/1538-4357/ac29c5","issue":"2","language":[{"iso":"eng"}],"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"day":"29","author":[{"first_name":"M.","last_name":"Renzo","full_name":"Renzo, M."},{"first_name":"Ylva Louise Linsdotter","last_name":"Götberg","full_name":"Götberg, Ylva Louise Linsdotter","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911"}],"article_number":"277","arxiv":1,"title":"Evolution of accretor stars in massive binaries: Broader implications from modeling ζ Ophiuchi","publisher":"American Astronomical Society","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_type":"original","article_processing_charge":"No","scopus_import":"1","publication":"The Astrophysical Journal"},{"publisher":"American Astronomical Society","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publication":"The Astrophysical Journal","article_type":"original","article_processing_charge":"No","scopus_import":"1","author":[{"full_name":"Wong, Tin Long Sunny","first_name":"Tin Long Sunny","last_name":"Wong"},{"first_name":"Josiah","last_name":"Schwab","full_name":"Schwab, Josiah"},{"first_name":"Ylva Louise Linsdotter","last_name":"Götberg","full_name":"Götberg, Ylva Louise Linsdotter","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911"}],"day":"03","article_number":"241","title":"Pre-explosion properties of Helium star donors to thermonuclear supernovae","arxiv":1,"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"issue":"2","language":[{"iso":"eng"}],"publication_identifier":{"issn":["0004-637X"],"eissn":["1538-4357"]},"doi":"10.3847/1538-4357/ac27ae","quality_controlled":"1","year":"2021","_id":"13454","month":"12","type":"journal_article","oa_version":"Preprint","date_updated":"2023-08-21T11:52:05Z","abstract":[{"text":"Helium star–carbon-oxygen white dwarf (CO WD) binaries are potential single-degenerate progenitor systems of thermonuclear supernovae. Revisiting a set of binary evolution calculations using the stellar evolution code MESA, we refine our previous predictions about which systems can lead to a thermonuclear supernova and then characterize the properties of the helium star donor at the time of explosion. We convert these model properties to near-UV/optical magnitudes assuming a blackbody spectrum and support this approach using a matched stellar atmosphere model. These models will be valuable to compare with pre-explosion imaging for future supernovae, though we emphasize the observational difficulty of detecting extremely blue companions. The pre-explosion source detected in association with SN 2012Z has been interpreted as a helium star binary containing an initially ultra-massive WD in a multiday orbit. However, extending our binary models to initial CO WD masses of up to 1.2 M⊙, we find that these systems undergo off-center carbon ignitions and thus are not expected to produce thermonuclear supernovae. This tension suggests that, if SN 2012Z is associated with a helium star–WD binary, then the pre-explosion optical light from the system must be significantly modified by the binary environment and/or the WD does not have a carbon-rich interior composition.","lang":"eng"}],"volume":922,"date_created":"2023-08-03T10:10:58Z","external_id":{"arxiv":["2109.14817"]},"status":"public","intvolume":"       922","extern":"1","citation":{"ama":"Wong TLS, Schwab J, Götberg YLL. Pre-explosion properties of Helium star donors to thermonuclear supernovae. <i>The Astrophysical Journal</i>. 2021;922(2). doi:<a href=\"https://doi.org/10.3847/1538-4357/ac27ae\">10.3847/1538-4357/ac27ae</a>","mla":"Wong, Tin Long Sunny, et al. “Pre-Explosion Properties of Helium Star Donors to Thermonuclear Supernovae.” <i>The Astrophysical Journal</i>, vol. 922, no. 2, 241, American Astronomical Society, 2021, doi:<a href=\"https://doi.org/10.3847/1538-4357/ac27ae\">10.3847/1538-4357/ac27ae</a>.","ista":"Wong TLS, Schwab J, Götberg YLL. 2021. Pre-explosion properties of Helium star donors to thermonuclear supernovae. The Astrophysical Journal. 922(2), 241.","apa":"Wong, T. L. S., Schwab, J., &#38; Götberg, Y. L. L. (2021). Pre-explosion properties of Helium star donors to thermonuclear supernovae. <i>The Astrophysical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-4357/ac27ae\">https://doi.org/10.3847/1538-4357/ac27ae</a>","ieee":"T. L. S. Wong, J. Schwab, and Y. L. L. Götberg, “Pre-explosion properties of Helium star donors to thermonuclear supernovae,” <i>The Astrophysical Journal</i>, vol. 922, no. 2. American Astronomical Society, 2021.","chicago":"Wong, Tin Long Sunny, Josiah Schwab, and Ylva Louise Linsdotter Götberg. “Pre-Explosion Properties of Helium Star Donors to Thermonuclear Supernovae.” <i>The Astrophysical Journal</i>. American Astronomical Society, 2021. <a href=\"https://doi.org/10.3847/1538-4357/ac27ae\">https://doi.org/10.3847/1538-4357/ac27ae</a>.","short":"T.L.S. Wong, J. Schwab, Y.L.L. Götberg, The Astrophysical Journal 922 (2021)."},"publication_status":"published","oa":1,"date_published":"2021-12-03T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2109.14817"}]},{"intvolume":"       656","citation":{"apa":"Laplace, E., Justham, S., Renzo, M., Götberg, Y. L. L., Farmer, R., Vartanyan, D., &#38; de Mink, S. E. (2021). Different to the core: The pre-supernova structures of massive single and binary-stripped stars. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202140506\">https://doi.org/10.1051/0004-6361/202140506</a>","mla":"Laplace, E., et al. “Different to the Core: The Pre-Supernova Structures of Massive Single and Binary-Stripped Stars.” <i>Astronomy &#38; Astrophysics</i>, vol. 656, A58, EDP Sciences, 2021, doi:<a href=\"https://doi.org/10.1051/0004-6361/202140506\">10.1051/0004-6361/202140506</a>.","ista":"Laplace E, Justham S, Renzo M, Götberg YLL, Farmer R, Vartanyan D, de Mink SE. 2021. Different to the core: The pre-supernova structures of massive single and binary-stripped stars. Astronomy &#38; Astrophysics. 656, A58.","ama":"Laplace E, Justham S, Renzo M, et al. Different to the core: The pre-supernova structures of massive single and binary-stripped stars. <i>Astronomy &#38; Astrophysics</i>. 2021;656. doi:<a href=\"https://doi.org/10.1051/0004-6361/202140506\">10.1051/0004-6361/202140506</a>","short":"E. Laplace, S. Justham, M. Renzo, Y.L.L. Götberg, R. Farmer, D. Vartanyan, S.E. de Mink, Astronomy &#38; Astrophysics 656 (2021).","chicago":"Laplace, E., S. Justham, M. Renzo, Ylva Louise Linsdotter Götberg, R. Farmer, D. Vartanyan, and S. E. de Mink. “Different to the Core: The Pre-Supernova Structures of Massive Single and Binary-Stripped Stars.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2021. <a href=\"https://doi.org/10.1051/0004-6361/202140506\">https://doi.org/10.1051/0004-6361/202140506</a>.","ieee":"E. Laplace <i>et al.</i>, “Different to the core: The pre-supernova structures of massive single and binary-stripped stars,” <i>Astronomy &#38; Astrophysics</i>, vol. 656. EDP Sciences, 2021."},"external_id":{"arxiv":["2102.05036"]},"status":"public","date_published":"2021-12-02T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://doi.org/10.1051/0004-6361/202140506"}],"oa":1,"publication_status":"published","_id":"13455","year":"2021","volume":656,"date_created":"2023-08-03T10:11:09Z","date_updated":"2023-08-21T11:49:15Z","abstract":[{"text":"The majority of massive stars live in binary or multiple systems and will interact with a companion during their lifetimes, which helps to explain the observed diversity of core-collapse supernovae. Donor stars in binary systems can lose most of their hydrogen-rich envelopes through mass transfer. As a result, not only are the surface properties affected, but so is the core structure. However, most calculations of the core-collapse properties of massive stars rely on single-star models. We present a systematic study of the difference between the pre-supernova structures of single stars and stars of the same initial mass (11–21 M⊙) that have been stripped due to stable post-main-sequence mass transfer at solar metallicity. We present the pre-supernova core composition with novel diagrams that give an intuitive representation of the isotope distribution. As shown in previous studies, at the edge of the carbon-oxygen core, the binary-stripped star models contain an extended gradient of carbon, oxygen, and neon. This layer remains until core collapse and is more extended in mass for higher initial stellar masses. It originates from the receding of the convective helium core during core helium burning in binary-stripped stars, which does not occur in single-star models. We find that this same evolutionary phase leads to systematic differences in the final density and nuclear energy generation profiles. Binary-stripped star models have systematically higher total masses of carbon at the moment of core collapse compared to single-star models, which likely results in systematically different supernova yields. In about half of our models, the silicon-burning and oxygen-rich layers merge after core silicon burning. We discuss the implications of our findings for the “explodability”, supernova observations, and nucleosynthesis of these stars. Our models are publicly available and can be readily used as input for detailed supernova simulations.","lang":"eng"}],"type":"journal_article","month":"12","oa_version":"Published Version","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"language":[{"iso":"eng"}],"doi":"10.1051/0004-6361/202140506","quality_controlled":"1","publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"publication":"Astronomy & Astrophysics","article_processing_charge":"No","scopus_import":"1","article_type":"original","publisher":"EDP Sciences","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","title":"Different to the core: The pre-supernova structures of massive single and binary-stripped stars","arxiv":1,"article_number":"A58","author":[{"first_name":"E.","last_name":"Laplace","full_name":"Laplace, E."},{"full_name":"Justham, S.","last_name":"Justham","first_name":"S."},{"full_name":"Renzo, M.","first_name":"M.","last_name":"Renzo"},{"full_name":"Götberg, Ylva Louise Linsdotter","orcid":"0000-0002-6960-6911","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","last_name":"Götberg","first_name":"Ylva Louise Linsdotter"},{"first_name":"R.","last_name":"Farmer","full_name":"Farmer, R."},{"first_name":"D.","last_name":"Vartanyan","full_name":"Vartanyan, D."},{"last_name":"de Mink","first_name":"S. E.","full_name":"de Mink, S. E."}],"day":"02"},{"oa":1,"publication_status":"published","main_file_link":[{"open_access":"1","url":"https://doi.org/10.3847/1538-4357/ac0af6"}],"date_published":"2021-08-27T00:00:00Z","external_id":{"arxiv":["2102.08408"]},"status":"public","citation":{"ama":"Berzin E, Secunda A, Cen R, Menegas A, Götberg YLL. Spectral signatures of population III and envelope-stripped stars in galaxies at the epoch of reionization. <i>The Astrophysical Journal</i>. 2021;918(1). doi:<a href=\"https://doi.org/10.3847/1538-4357/ac0af6\">10.3847/1538-4357/ac0af6</a>","apa":"Berzin, E., Secunda, A., Cen, R., Menegas, A., &#38; Götberg, Y. L. L. (2021). Spectral signatures of population III and envelope-stripped stars in galaxies at the epoch of reionization. <i>The Astrophysical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-4357/ac0af6\">https://doi.org/10.3847/1538-4357/ac0af6</a>","mla":"Berzin, Elizabeth, et al. “Spectral Signatures of Population III and Envelope-Stripped Stars in Galaxies at the Epoch of Reionization.” <i>The Astrophysical Journal</i>, vol. 918, no. 1, 5, American Astronomical Society, 2021, doi:<a href=\"https://doi.org/10.3847/1538-4357/ac0af6\">10.3847/1538-4357/ac0af6</a>.","ista":"Berzin E, Secunda A, Cen R, Menegas A, Götberg YLL. 2021. Spectral signatures of population III and envelope-stripped stars in galaxies at the epoch of reionization. The Astrophysical Journal. 918(1), 5.","chicago":"Berzin, Elizabeth, Amy Secunda, Renyue Cen, Alexander Menegas, and Ylva Louise Linsdotter Götberg. “Spectral Signatures of Population III and Envelope-Stripped Stars in Galaxies at the Epoch of Reionization.” <i>The Astrophysical Journal</i>. American Astronomical Society, 2021. <a href=\"https://doi.org/10.3847/1538-4357/ac0af6\">https://doi.org/10.3847/1538-4357/ac0af6</a>.","ieee":"E. Berzin, A. Secunda, R. Cen, A. Menegas, and Y. L. L. Götberg, “Spectral signatures of population III and envelope-stripped stars in galaxies at the epoch of reionization,” <i>The Astrophysical Journal</i>, vol. 918, no. 1. American Astronomical Society, 2021.","short":"E. Berzin, A. Secunda, R. Cen, A. Menegas, Y.L.L. Götberg, The Astrophysical Journal 918 (2021)."},"intvolume":"       918","extern":"1","month":"08","oa_version":"Published Version","type":"journal_article","abstract":[{"text":"While most simulations of the epoch of reionization have focused on single-stellar populations in star-forming dwarf galaxies, products of binary evolution are expected to significantly contribute to emissions of hydrogen-ionizing photons. Among these products are stripped stars (or helium stars), which have their envelopes stripped from interactions with binary companions, leaving an exposed helium core. Previous work has suggested these stripped stars can dominate the Lyman Continuum (LyC) photon output of high-redshift, low-luminosity galaxies post-starburst. Other sources of hard radiation in the early universe include zero-metallicity Population iii stars, which may have similar spectral energy distribution (SED) properties to galaxies with radiation dominated by stripped-star emissions. Here, we use four metrics (the power-law exponent over wavelength intervals 240–500 Å, 600–900 Å, and 1200–2000 Å, and the ratio of total luminosity in FUV wavelengths to LyC wavelengths) to compare the SEDs of simulated galaxies with only single-stellar evolution, galaxies containing stripped stars, and galaxies containing Population iii stars, with four different initial mass functions (IMFs). We find that stripped stars significantly alter SEDs in the LyC range of galaxies at the epoch of reionization. SEDs in galaxies with stripped stars have lower power-law indices in the LyC range and lower FUV to LyC luminosity ratios. These differences in SEDs are present at all considered luminosities (${M}_{\\mathrm{UV}}\\gt -15$, AB system), and are most pronounced for lower-luminosity galaxies. Intrinsic SEDs as well as those with interstellar medium absorption of galaxies with stripped stars and Population iii stars are found to be distinct for all tested Population iii IMFs.","lang":"eng"}],"date_updated":"2023-08-21T11:44:50Z","date_created":"2023-08-03T10:11:24Z","volume":918,"year":"2021","_id":"13456","publication_identifier":{"eissn":["1538-4357"],"issn":["0004-637X"]},"quality_controlled":"1","doi":"10.3847/1538-4357/ac0af6","issue":"1","language":[{"iso":"eng"}],"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"day":"27","author":[{"last_name":"Berzin","first_name":"Elizabeth","full_name":"Berzin, Elizabeth"},{"first_name":"Amy","last_name":"Secunda","full_name":"Secunda, Amy"},{"last_name":"Cen","first_name":"Renyue","full_name":"Cen, Renyue"},{"full_name":"Menegas, Alexander","first_name":"Alexander","last_name":"Menegas"},{"first_name":"Ylva Louise Linsdotter","last_name":"Götberg","orcid":"0000-0002-6960-6911","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","full_name":"Götberg, Ylva Louise Linsdotter"}],"article_number":"5","arxiv":1,"title":"Spectral signatures of population III and envelope-stripped stars in galaxies at the epoch of reionization","publisher":"American Astronomical Society","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_type":"original","article_processing_charge":"No","scopus_import":"1","publication":"The Astrophysical Journal"},{"year":"2021","_id":"13457","month":"08","oa_version":"Published Version","type":"journal_article","date_updated":"2023-08-21T11:49:36Z","abstract":[{"text":"Context. Observations of massive stars in open clusters younger than ∼8 Myr have shown that a majority of them are in binary systems, most of which will interact during their life. While these can be used as a proxy of the initial multiplicity properties, studying populations of massive stars older than ∼20 Myr allows us to probe the outcome of these interactions after a significant number of systems have experienced mass and angular momentum transfer and may even have merged.\r\n\r\nAims. Using multi-epoch integral-field spectroscopy, we aim to investigate the multiplicity properties of the massive-star population in the dense core of the ∼40 Myr old cluster NGC 330 in the Small Magellanic Cloud in order to search for possible imprints of stellar evolution on the multiplicity properties.\r\n\r\nMethods. We obtained six epochs of VLT/MUSE observations operated in wide-field mode with the extended wavelength setup and supported by adaptive optics. We extracted spectra and measured radial velocities for stars brighter than mF814W = 19. We identified single-lined spectroscopic binaries through significant RV variability with a peak-to-peak amplitude larger than 20 km s−1. We also identified double-lined spectroscopic binaries, and quantified the observational biases for binary detection. In particular, we took into account that binary systems with similar line strengths are difficult to detect in our data set.\r\n\r\nResults. The observed spectroscopic binary fraction among stars brighter than mF814W = 19 (approximately 5.5 M⊙ on the main sequence) is fSBobs = 13.2 ± 2.0%. Considering period and mass ratio ranges from log(P) = 0.15−3.5 (about 1.4 to 3160 d), q = 0.1−1.0, and a representative set of orbital parameter distributions, we find a bias-corrected close binary fraction of fcl = 34−7+8%. This fraction seems to decline for the fainter stars, which indicates either that the close binary fraction drops in the B-type domain, or that the period distribution becomes more heavily weighted toward longer orbital periods. We further find that both fractions vary strongly in different regions of the color-magnitude diagram, which corresponds to different evolutionary stages. This probably reveals the imprint of the binary history of different groups of stars. In particular, we find that the observed spectroscopic binary fraction of Be stars (fSBobs = 2 ± 2%) is significantly lower than that of B-type stars (fSBobs = 9 ± 2%).\r\n\r\nConclusions. We provide the first homogeneous radial velocity study of a large sample of B-type stars at a low metallicity ([Fe/H] ≲ −1.0). The overall bias-corrected close binary fraction (log(P) < 3.5 d) of the B-star population in NGC 330 is lower than the fraction reported for younger Galactic and Large Magellanic Cloud clusters in previous works. More data are needed, however, to establish whether the observed differences are caused by an age or a metallicity effect.","lang":"eng"}],"date_created":"2023-08-03T10:11:34Z","volume":652,"external_id":{"arxiv":["2104.13409"]},"status":"public","citation":{"mla":"Bodensteiner, J., et al. “The Young Massive SMC Cluster NGC 330 Seen by MUSE. II. Multiplicity Properties of the Massive-Star Population.” <i>Astronomy &#38; Astrophysics</i>, vol. 652, A70, EDP Sciences, 2021, doi:<a href=\"https://doi.org/10.1051/0004-6361/202140507\">10.1051/0004-6361/202140507</a>.","ista":"Bodensteiner J, Sana H, Wang C, Langer N, Mahy L, Banyard G, de Koter A, de Mink SE, Evans CJ, Götberg YLL, Patrick LR, Schneider FRN, Tramper F. 2021. The young massive SMC cluster NGC 330 seen by MUSE. II. Multiplicity properties of the massive-star population. Astronomy &#38; Astrophysics. 652, A70.","apa":"Bodensteiner, J., Sana, H., Wang, C., Langer, N., Mahy, L., Banyard, G., … Tramper, F. (2021). The young massive SMC cluster NGC 330 seen by MUSE. II. Multiplicity properties of the massive-star population. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202140507\">https://doi.org/10.1051/0004-6361/202140507</a>","ama":"Bodensteiner J, Sana H, Wang C, et al. The young massive SMC cluster NGC 330 seen by MUSE. II. Multiplicity properties of the massive-star population. <i>Astronomy &#38; Astrophysics</i>. 2021;652. doi:<a href=\"https://doi.org/10.1051/0004-6361/202140507\">10.1051/0004-6361/202140507</a>","short":"J. Bodensteiner, H. Sana, C. Wang, N. Langer, L. Mahy, G. Banyard, A. de Koter, S.E. de Mink, C.J. Evans, Y.L.L. Götberg, L.R. Patrick, F.R.N. Schneider, F. Tramper, Astronomy &#38; Astrophysics 652 (2021).","ieee":"J. Bodensteiner <i>et al.</i>, “The young massive SMC cluster NGC 330 seen by MUSE. II. Multiplicity properties of the massive-star population,” <i>Astronomy &#38; Astrophysics</i>, vol. 652. EDP Sciences, 2021.","chicago":"Bodensteiner, J., H. Sana, C. Wang, N. Langer, L. Mahy, G. Banyard, A. de Koter, et al. “The Young Massive SMC Cluster NGC 330 Seen by MUSE. II. Multiplicity Properties of the Massive-Star Population.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2021. <a href=\"https://doi.org/10.1051/0004-6361/202140507\">https://doi.org/10.1051/0004-6361/202140507</a>."},"extern":"1","intvolume":"       652","publication_status":"published","oa":1,"main_file_link":[{"url":"https://doi.org/10.1051/0004-6361/202140507","open_access":"1"}],"date_published":"2021-08-12T00:00:00Z","publisher":"EDP Sciences","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_type":"original","scopus_import":"1","article_processing_charge":"No","publication":"Astronomy & Astrophysics","day":"12","author":[{"first_name":"J.","last_name":"Bodensteiner","full_name":"Bodensteiner, J."},{"full_name":"Sana, H.","first_name":"H.","last_name":"Sana"},{"full_name":"Wang, C.","last_name":"Wang","first_name":"C."},{"first_name":"N.","last_name":"Langer","full_name":"Langer, N."},{"full_name":"Mahy, L.","first_name":"L.","last_name":"Mahy"},{"first_name":"G.","last_name":"Banyard","full_name":"Banyard, G."},{"full_name":"de Koter, A.","last_name":"de Koter","first_name":"A."},{"last_name":"de Mink","first_name":"S. E.","full_name":"de Mink, S. E."},{"last_name":"Evans","first_name":"C. J.","full_name":"Evans, C. J."},{"id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911","full_name":"Götberg, Ylva Louise Linsdotter","last_name":"Götberg","first_name":"Ylva Louise Linsdotter"},{"first_name":"L. R.","last_name":"Patrick","full_name":"Patrick, L. R."},{"full_name":"Schneider, F. R. N.","first_name":"F. R. N.","last_name":"Schneider"},{"last_name":"Tramper","first_name":"F.","full_name":"Tramper, F."}],"article_number":"A70","arxiv":1,"title":"The young massive SMC cluster NGC 330 seen by MUSE. II. Multiplicity properties of the massive-star population","language":[{"iso":"eng"}],"keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"publication_identifier":{"issn":["0004-6361"],"eissn":["1432-0746"]},"quality_controlled":"1","doi":"10.1051/0004-6361/202140507"},{"author":[{"first_name":"David","last_name":"Vartanyan","full_name":"Vartanyan, David"},{"full_name":"Laplace, Eva","first_name":"Eva","last_name":"Laplace"},{"last_name":"Renzo","first_name":"Mathieu","full_name":"Renzo, Mathieu"},{"full_name":"Götberg, Ylva Louise Linsdotter","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911","first_name":"Ylva Louise Linsdotter","last_name":"Götberg"},{"first_name":"Adam","last_name":"Burrows","full_name":"Burrows, Adam"},{"full_name":"de Mink, Selma E.","first_name":"Selma E.","last_name":"de Mink"}],"day":"23","article_number":"L5","arxiv":1,"title":"Binary-stripped stars as core-collapse supernovae progenitors","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publisher":"American Astronomical Society","publication":"The Astrophysical Journal Letters","article_type":"original","scopus_import":"1","article_processing_charge":"No","publication_identifier":{"eissn":["2041-8213"],"issn":["2041-8205"]},"doi":"10.3847/2041-8213/ac0b42","quality_controlled":"1","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"issue":"1","language":[{"iso":"eng"}],"oa_version":"Preprint","type":"journal_article","month":"07","date_updated":"2023-08-21T11:37:48Z","abstract":[{"text":"Most massive stars experience binary interactions in their lifetimes that can alter both the surface and core structure of the stripped star with significant effects on their ultimate fate as core-collapse supernovae. However, core-collapse supernovae simulations to date have focused almost exclusively on the evolution of single stars. We present a systematic simulation study of single and binary-stripped stars with the same initial mass as candidates for core-collapse supernovae (11–21 M⊙). Generally, we find that binary-stripped stars core tend to have a smaller compactness parameter, with a more prominent, deeper silicon/oxygen interface, and explode preferentially to the corresponding single stars of the same initial mass. Such a dichotomy of behavior between these two modes of evolution would have important implications for supernovae statistics, including the final neutron star masses, explosion energies, and nucleosynthetic yields. Binary-stripped remnants are also well poised to populate the possible mass gap between the heaviest neutron stars and the lightest black holes. Our work presents an improvement along two fronts, as we self-consistently account for the pre-collapse stellar evolution and the subsequent explosion outcome. Even so, our results emphasize the need for more detailed stellar evolutionary models to capture the sensitive nature of explosion outcome.","lang":"eng"}],"volume":916,"date_created":"2023-08-03T10:11:45Z","year":"2021","_id":"13458","publication_status":"published","oa":1,"date_published":"2021-07-23T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2104.03317"}],"external_id":{"arxiv":["2104.03317"]},"status":"public","intvolume":"       916","extern":"1","citation":{"short":"D. Vartanyan, E. Laplace, M. Renzo, Y.L.L. Götberg, A. Burrows, S.E. de Mink, The Astrophysical Journal Letters 916 (2021).","chicago":"Vartanyan, David, Eva Laplace, Mathieu Renzo, Ylva Louise Linsdotter Götberg, Adam Burrows, and Selma E. de Mink. “Binary-Stripped Stars as Core-Collapse Supernovae Progenitors.” <i>The Astrophysical Journal Letters</i>. American Astronomical Society, 2021. <a href=\"https://doi.org/10.3847/2041-8213/ac0b42\">https://doi.org/10.3847/2041-8213/ac0b42</a>.","ieee":"D. Vartanyan, E. Laplace, M. Renzo, Y. L. L. Götberg, A. Burrows, and S. E. de Mink, “Binary-stripped stars as core-collapse supernovae progenitors,” <i>The Astrophysical Journal Letters</i>, vol. 916, no. 1. American Astronomical Society, 2021.","apa":"Vartanyan, D., Laplace, E., Renzo, M., Götberg, Y. L. L., Burrows, A., &#38; de Mink, S. E. (2021). Binary-stripped stars as core-collapse supernovae progenitors. <i>The Astrophysical Journal Letters</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/2041-8213/ac0b42\">https://doi.org/10.3847/2041-8213/ac0b42</a>","mla":"Vartanyan, David, et al. “Binary-Stripped Stars as Core-Collapse Supernovae Progenitors.” <i>The Astrophysical Journal Letters</i>, vol. 916, no. 1, L5, American Astronomical Society, 2021, doi:<a href=\"https://doi.org/10.3847/2041-8213/ac0b42\">10.3847/2041-8213/ac0b42</a>.","ista":"Vartanyan D, Laplace E, Renzo M, Götberg YLL, Burrows A, de Mink SE. 2021. Binary-stripped stars as core-collapse supernovae progenitors. The Astrophysical Journal Letters. 916(1), L5.","ama":"Vartanyan D, Laplace E, Renzo M, Götberg YLL, Burrows A, de Mink SE. Binary-stripped stars as core-collapse supernovae progenitors. <i>The Astrophysical Journal Letters</i>. 2021;916(1). doi:<a href=\"https://doi.org/10.3847/2041-8213/ac0b42\">10.3847/2041-8213/ac0b42</a>"}},{"publication_identifier":{"issn":["0004-6256"],"eissn":["1538-3881"]},"doi":"10.3847/1538-3881/abf144","quality_controlled":"1","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"language":[{"iso":"eng"}],"issue":"5","author":[{"last_name":"Wang","first_name":"Luqian","full_name":"Wang, Luqian"},{"first_name":"Douglas R.","last_name":"Gies","full_name":"Gies, Douglas R."},{"first_name":"Geraldine J.","last_name":"Peters","full_name":"Peters, Geraldine J."},{"first_name":"Ylva Louise Linsdotter","last_name":"Götberg","full_name":"Götberg, Ylva Louise Linsdotter","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911"},{"last_name":"Chojnowski","first_name":"S. Drew","full_name":"Chojnowski, S. Drew"},{"full_name":"Lester, Kathryn V.","first_name":"Kathryn V.","last_name":"Lester"},{"last_name":"Howell","first_name":"Steve B.","full_name":"Howell, Steve B."}],"day":"04","title":"The detection and characterization of Be+sdO binaries from HST/STIS FUV spectroscopy","arxiv":1,"article_number":"248","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publisher":"American Astronomical Society","publication":"The Astronomical Journal","scopus_import":"1","article_processing_charge":"No","article_type":"original","oa":1,"publication_status":"published","date_published":"2021-05-04T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2103.13642"}],"external_id":{"arxiv":["2103.13642"]},"status":"public","extern":"1","intvolume":"       161","citation":{"ista":"Wang L, Gies DR, Peters GJ, Götberg YLL, Chojnowski SD, Lester KV, Howell SB. 2021. The detection and characterization of Be+sdO binaries from HST/STIS FUV spectroscopy. The Astronomical Journal. 161(5), 248.","mla":"Wang, Luqian, et al. “The Detection and Characterization of Be+sdO Binaries from HST/STIS FUV Spectroscopy.” <i>The Astronomical Journal</i>, vol. 161, no. 5, 248, American Astronomical Society, 2021, doi:<a href=\"https://doi.org/10.3847/1538-3881/abf144\">10.3847/1538-3881/abf144</a>.","apa":"Wang, L., Gies, D. R., Peters, G. J., Götberg, Y. L. L., Chojnowski, S. D., Lester, K. V., &#38; Howell, S. B. (2021). The detection and characterization of Be+sdO binaries from HST/STIS FUV spectroscopy. <i>The Astronomical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-3881/abf144\">https://doi.org/10.3847/1538-3881/abf144</a>","ama":"Wang L, Gies DR, Peters GJ, et al. The detection and characterization of Be+sdO binaries from HST/STIS FUV spectroscopy. <i>The Astronomical Journal</i>. 2021;161(5). doi:<a href=\"https://doi.org/10.3847/1538-3881/abf144\">10.3847/1538-3881/abf144</a>","short":"L. Wang, D.R. Gies, G.J. Peters, Y.L.L. Götberg, S.D. Chojnowski, K.V. Lester, S.B. Howell, The Astronomical Journal 161 (2021).","ieee":"L. Wang <i>et al.</i>, “The detection and characterization of Be+sdO binaries from HST/STIS FUV spectroscopy,” <i>The Astronomical Journal</i>, vol. 161, no. 5. American Astronomical Society, 2021.","chicago":"Wang, Luqian, Douglas R. Gies, Geraldine J. Peters, Ylva Louise Linsdotter Götberg, S. Drew Chojnowski, Kathryn V. Lester, and Steve B. Howell. “The Detection and Characterization of Be+sdO Binaries from HST/STIS FUV Spectroscopy.” <i>The Astronomical Journal</i>. American Astronomical Society, 2021. <a href=\"https://doi.org/10.3847/1538-3881/abf144\">https://doi.org/10.3847/1538-3881/abf144</a>."},"date_updated":"2023-08-21T11:35:50Z","abstract":[{"lang":"eng","text":"The B emission-line stars are rapid rotators that were probably spun up by mass and angular momentum accretion through mass transfer in an interacting binary. Mass transfer will strip the donor star of its envelope to create a small and hot subdwarf remnant. Here we report on Hubble Space Telescope/STIS far-ultraviolet spectroscopy of a sample of Be stars that reveals the presence of the hot sdO companion through the calculation of cross-correlation functions of the observed and model spectra. We clearly detect the spectral signature of the sdO star in 10 of the 13 stars in the sample, and the spectral signals indicate that the sdO stars are hot, relatively faint, and slowly rotating as predicted by models. A comparison of their temperatures and radii with evolutionary tracks indicates that the sdO stars occupy the relatively long-lived, He-core burning stage. Only 1 of the 10 detections was a known binary prior to this investigation, which emphasizes the difficulty of finding such Be+sdO binaries through optical spectroscopy. However, these results and others indicate that many Be stars probably host hot subdwarf companions."}],"oa_version":"Preprint","month":"05","type":"journal_article","volume":161,"date_created":"2023-08-03T10:11:57Z","year":"2021","_id":"13459"},{"doi":"10.48550/arXiv.2111.15608","date_published":"2021-11-30T00:00:00Z","main_file_link":[{"url":" https://doi.org/10.48550/arXiv.2111.15608","open_access":"1"}],"oa":1,"publication_status":"submitted","extern":"1","citation":{"ieee":"S. R. Kulkarni <i>et al.</i>, “Science with the ultraviolet explorer (UVEX),” <i>arXiv</i>. .","chicago":"Kulkarni, S. R., Fiona A. Harrison, Brian W. Grefenstette, Hannah P. Earnshaw, Igor Andreoni, Danielle A. Berg, Joshua S. Bloom, et al. “Science with the Ultraviolet Explorer (UVEX).” <i>ArXiv</i>, n.d. <a href=\"https://doi.org/10.48550/arXiv.2111.15608\">https://doi.org/10.48550/arXiv.2111.15608</a>.","short":"S.R. Kulkarni, F.A. Harrison, B.W. Grefenstette, H.P. Earnshaw, I. Andreoni, D.A. Berg, J.S. Bloom, S.B. Cenko, R. Chornock, J.L. Christiansen, M.W. Coughlin, A.W. Criswell, B. Darvish, K.K. Das, K. De, L. Dessart, D. Dixon, B. Dorsman, K.E.-B. Kareem El-Badry, C. Evans, K.E.S. Ford, C. Fremling, B.T. Gansicke, S. Gezari, Y.L.L. Götberg, G.M. Green, M.J. Graham, M. Heida, A.Y.Q. Ho, A.D. Jaodand, C.M.J.-K. Christopher M. Johns-Krull, M.M. Kasliwal, M. Lazzarini, W. Lu, R. Margutti, D.C. Martin, D.C. Masters, B. McKernan, Y. Naze, S.M. Nissanke, B. Parazin, D.A. Perley, E.S. Phinney, A.L. Piro, G. Raaijmakers, G. Rauw, A.C. Rodriguez, H. Sana, P. Senchyna, L.P. Singer, J.J. Spake, K.G. Stassun, D. Stern, H.I. Teplitz, D.R. Weisz, Y. Yao, ArXiv (n.d.).","ama":"Kulkarni SR, Harrison FA, Grefenstette BW, et al. Science with the ultraviolet explorer (UVEX). <i>arXiv</i>. doi:<a href=\"https://doi.org/10.48550/arXiv.2111.15608\">10.48550/arXiv.2111.15608</a>","mla":"Kulkarni, S. R., et al. “Science with the Ultraviolet Explorer (UVEX).” <i>ArXiv</i>, 2111.15608, doi:<a href=\"https://doi.org/10.48550/arXiv.2111.15608\">10.48550/arXiv.2111.15608</a>.","ista":"Kulkarni SR, Harrison FA, Grefenstette BW, Earnshaw HP, Andreoni I, Berg DA, Bloom JS, Cenko SB, Chornock R, Christiansen JL, Coughlin MW, Criswell AW, Darvish B, Das KK, De K, Dessart L, Dixon D, Dorsman B, Kareem El-Badry KE-B, Evans C, Ford KES, Fremling C, Gansicke BT, Gezari S, Götberg YLL, Green GM, Graham MJ, Heida M, Ho AYQ, Jaodand AD, Christopher M. Johns-Krull CMJ-K, Kasliwal MM, Lazzarini M, Lu W, Margutti R, Martin DC, Masters DC, McKernan B, Naze Y, Nissanke SM, Parazin B, Perley DA, Phinney ES, Piro AL, Raaijmakers G, Rauw G, Rodriguez AC, Sana H, Senchyna P, Singer LP, Spake JJ, Stassun KG, Stern D, Teplitz HI, Weisz DR, Yao Y. Science with the ultraviolet explorer (UVEX). arXiv, 2111.15608.","apa":"Kulkarni, S. R., Harrison, F. A., Grefenstette, B. W., Earnshaw, H. P., Andreoni, I., Berg, D. A., … Yao, Y. (n.d.). Science with the ultraviolet explorer (UVEX). <i>arXiv</i>. <a href=\"https://doi.org/10.48550/arXiv.2111.15608\">https://doi.org/10.48550/arXiv.2111.15608</a>"},"language":[{"iso":"eng"}],"external_id":{"arxiv":["2111.15608"]},"status":"public","article_number":"2111.15608","title":"Science with the ultraviolet explorer (UVEX)","arxiv":1,"date_created":"2023-08-21T10:11:00Z","author":[{"last_name":"Kulkarni","first_name":"S. R.","full_name":"Kulkarni, S. R."},{"first_name":"Fiona A.","last_name":"Harrison","full_name":"Harrison, Fiona A."},{"full_name":"Grefenstette, Brian W.","first_name":"Brian W.","last_name":"Grefenstette"},{"full_name":"Earnshaw, Hannah P.","last_name":"Earnshaw","first_name":"Hannah P."},{"full_name":"Andreoni, Igor","first_name":"Igor","last_name":"Andreoni"},{"full_name":"Berg, Danielle A.","last_name":"Berg","first_name":"Danielle A."},{"first_name":"Joshua S.","last_name":"Bloom","full_name":"Bloom, Joshua S."},{"full_name":"Cenko, S. Bradley","first_name":"S. Bradley","last_name":"Cenko"},{"last_name":"Chornock","first_name":"Ryan","full_name":"Chornock, Ryan"},{"full_name":"Christiansen, Jessie L.","last_name":"Christiansen","first_name":"Jessie L."},{"full_name":"Coughlin, Michael W.","first_name":"Michael W.","last_name":"Coughlin"},{"last_name":"Criswell","first_name":"Alexander Wuollet","full_name":"Criswell, Alexander Wuollet"},{"first_name":"Behnam","last_name":"Darvish","full_name":"Darvish, Behnam"},{"full_name":"Das, Kaustav K.","last_name":"Das","first_name":"Kaustav K."},{"full_name":"De, Kishalay","last_name":"De","first_name":"Kishalay"},{"full_name":"Dessart, Luc","first_name":"Luc","last_name":"Dessart"},{"first_name":"Don","last_name":"Dixon","full_name":"Dixon, Don"},{"last_name":"Dorsman","first_name":"Bas","full_name":"Dorsman, Bas"},{"full_name":"Kareem El-Badry, Kareem El-Badry","last_name":"Kareem El-Badry","first_name":"Kareem El-Badry"},{"first_name":"Christopher","last_name":"Evans","full_name":"Evans, Christopher"},{"first_name":"K. E. Saavik","last_name":"Ford","full_name":"Ford, K. E. Saavik"},{"first_name":"Christoffer","last_name":"Fremling","full_name":"Fremling, Christoffer"},{"full_name":"Gansicke, Boris T.","last_name":"Gansicke","first_name":"Boris T."},{"first_name":"Suvi","last_name":"Gezari","full_name":"Gezari, Suvi"},{"last_name":"Götberg","first_name":"Ylva Louise Linsdotter","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911","full_name":"Götberg, Ylva Louise Linsdotter"},{"full_name":"Green, Gregory M.","first_name":"Gregory M.","last_name":"Green"},{"full_name":"Graham, Matthew J.","first_name":"Matthew J.","last_name":"Graham"},{"full_name":"Heida, Marianne","first_name":"Marianne","last_name":"Heida"},{"first_name":"Anna Y. Q.","last_name":"Ho","full_name":"Ho, Anna Y. Q."},{"first_name":"Amruta D.","last_name":"Jaodand","full_name":"Jaodand, Amruta D."},{"full_name":"Christopher M. Johns-Krull, Christopher M. Johns-Krull","first_name":"Christopher M. Johns-Krull","last_name":"Christopher M. Johns-Krull"},{"last_name":"Kasliwal","first_name":"Mansi M.","full_name":"Kasliwal, Mansi M."},{"full_name":"Lazzarini, Margaret","first_name":"Margaret","last_name":"Lazzarini"},{"first_name":"Wenbin","last_name":"Lu","full_name":"Lu, Wenbin"},{"first_name":"Raffaella","last_name":"Margutti","full_name":"Margutti, Raffaella"},{"full_name":"Martin, D. Christopher","last_name":"Martin","first_name":"D. Christopher"},{"first_name":"Daniel Charles","last_name":"Masters","full_name":"Masters, Daniel Charles"},{"first_name":"Barry","last_name":"McKernan","full_name":"McKernan, Barry"},{"last_name":"Naze","first_name":"Yael","full_name":"Naze, Yael"},{"full_name":"Nissanke, Samaya M.","first_name":"Samaya M.","last_name":"Nissanke"},{"last_name":"Parazin","first_name":"B.","full_name":"Parazin, B."},{"full_name":"Perley, Daniel A.","first_name":"Daniel A.","last_name":"Perley"},{"first_name":"E. Sterl","last_name":"Phinney","full_name":"Phinney, E. Sterl"},{"full_name":"Piro, Anthony L.","last_name":"Piro","first_name":"Anthony L."},{"last_name":"Raaijmakers","first_name":"G.","full_name":"Raaijmakers, G."},{"full_name":"Rauw, Gregor","first_name":"Gregor","last_name":"Rauw"},{"full_name":"Rodriguez, Antonio C.","last_name":"Rodriguez","first_name":"Antonio C."},{"full_name":"Sana, Hugues","first_name":"Hugues","last_name":"Sana"},{"first_name":"Peter","last_name":"Senchyna","full_name":"Senchyna, Peter"},{"full_name":"Singer, Leo P.","first_name":"Leo P.","last_name":"Singer"},{"first_name":"Jessica J.","last_name":"Spake","full_name":"Spake, Jessica J."},{"full_name":"Stassun, Keivan G.","first_name":"Keivan G.","last_name":"Stassun"},{"last_name":"Stern","first_name":"Daniel","full_name":"Stern, Daniel"},{"first_name":"Harry I.","last_name":"Teplitz","full_name":"Teplitz, Harry I."},{"full_name":"Weisz, Daniel R.","first_name":"Daniel R.","last_name":"Weisz"},{"first_name":"Yuhan","last_name":"Yao","full_name":"Yao, Yuhan"}],"type":"preprint","month":"11","oa_version":"Preprint","day":"30","date_updated":"2023-08-22T13:15:02Z","abstract":[{"text":"UVEX is a proposed medium class Explorer mission designed to provide crucial missing capabilities that will address objectives central to a broad range of modern astrophysics. The UVEX design has two co-aligned wide-field imagers operating in the FUV and NUV and a powerful broadband medium resolution spectrometer. In its two-year baseline mission, UVEX will perform a multi-cadence synoptic all-sky survey 50/100 times deeper than GALEX in the NUV/FUV, cadenced surveys of the Large and Small Magellanic Clouds, rapid target of opportunity followup, as well as spectroscopic followup of samples of stars and galaxies. The science program is built around three pillars. First, UVEX will explore the low-mass, low-metallicity galaxy frontier through imaging and spectroscopic surveys that will probe key aspects of the evolution of galaxies by understanding how star formation and stellar evolution at low metallicities affect the growth and evolution of low-metallicity, low-mass galaxies in the local universe. Such galaxies contain half the mass in the local universe, and are analogs for the first galaxies, but observed at distances that make them accessible to detailed study. Second, UVEX will explore the dynamic universe through time-domain surveys and prompt spectroscopic followup capability will probe the environments, energetics, and emission processes in the early aftermaths of gravitational wave-discovered compact object mergers, discover hot, fast UV transients, and diagnose the early stages of stellar explosions. Finally, UVEX will become a key community resource by leaving a large all-sky legacy data set, enabling a wide range of scientific studies and filling a gap in the new generation of wide-field, sensitive optical and infrared surveys provided by the Rubin, Euclid, and Roman observatories. This paper discusses the scientific potential of UVEX, and the broad scientific program.","lang":"eng"}],"_id":"14097","publication":"arXiv","article_processing_charge":"No","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","year":"2021"},{"publisher":"American Astronomical Society","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publication":"The Astrophysical Journal","article_processing_charge":"No","scopus_import":"1","article_type":"original","author":[{"last_name":"Götberg","first_name":"Ylva Louise Linsdotter","full_name":"Götberg, Ylva Louise Linsdotter","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911"},{"first_name":"V.","last_name":"Korol","full_name":"Korol, V."},{"first_name":"A.","last_name":"Lamberts","full_name":"Lamberts, A."},{"full_name":"Kupfer, T.","first_name":"T.","last_name":"Kupfer"},{"last_name":"Breivik","first_name":"K.","full_name":"Breivik, K."},{"full_name":"Ludwig, B.","last_name":"Ludwig","first_name":"B."},{"last_name":"Drout","first_name":"M. R.","full_name":"Drout, M. R."}],"day":"20","title":"Stars stripped in binaries: The living gravitational-wave sources","arxiv":1,"article_number":"56","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"language":[{"iso":"eng"}],"issue":"1","publication_identifier":{"issn":["0004-637X"],"eissn":["1538-4357"]},"doi":"10.3847/1538-4357/abbda5","quality_controlled":"1","year":"2020","_id":"13460","abstract":[{"text":"Binary interaction can cause stellar envelopes to be stripped, which significantly reduces the radius of the star. The orbit of a binary composed of a stripped star and a compact object can therefore be so tight that the gravitational radiation the system produces reaches frequencies accessible to the Laser Interferometer Space Antenna (LISA). Two such stripped stars in tight orbits with white dwarfs are known so far (ZTF J2130+4420 and CD−30°11223), but many more are expected to exist. These binaries provide important constraints for binary evolution models and may be used as LISA verification sources. We develop a Monte Carlo code that uses detailed evolutionary models to simulate the Galactic population of stripped stars in tight orbits with either neutron star or white dwarf companions. We predict 0–100 stripped star + white dwarf binaries and 0–4 stripped star + neutron star binaries with a signal-to-noise ratio >5 after 10 yr of observations with LISA. More than 90% of these binaries are expected to show large radial velocity shifts of ≳200 $\\,\\mathrm{km}\\,{{\\rm{s}}}^{-1}$, which are spectroscopically detectable. Photometric variability due to tidal deformation of the stripped star is also expected and has been observed in ZTF J2130+4420 and CD−30°11223. In addition, the stripped star + neutron star binaries are expected to be X-ray bright with LX ≳ 1033–1036 $\\,\\mathrm{erg}\\,{{\\rm{s}}}^{-1}$. Our results show that stripped star binaries are promising multimessenger sources for the upcoming electromagnetic and gravitational wave facilities.","lang":"eng"}],"date_updated":"2023-08-21T11:32:40Z","oa_version":"Preprint","month":"11","type":"journal_article","volume":904,"date_created":"2023-08-03T10:12:07Z","status":"public","external_id":{"arxiv":["2006.07382"]},"intvolume":"       904","extern":"1","citation":{"short":"Y.L.L. Götberg, V. Korol, A. Lamberts, T. Kupfer, K. Breivik, B. Ludwig, M.R. Drout, The Astrophysical Journal 904 (2020).","chicago":"Götberg, Ylva Louise Linsdotter, V. Korol, A. Lamberts, T. Kupfer, K. Breivik, B. Ludwig, and M. R. Drout. “Stars Stripped in Binaries: The Living Gravitational-Wave Sources.” <i>The Astrophysical Journal</i>. American Astronomical Society, 2020. <a href=\"https://doi.org/10.3847/1538-4357/abbda5\">https://doi.org/10.3847/1538-4357/abbda5</a>.","ieee":"Y. L. L. Götberg <i>et al.</i>, “Stars stripped in binaries: The living gravitational-wave sources,” <i>The Astrophysical Journal</i>, vol. 904, no. 1. American Astronomical Society, 2020.","apa":"Götberg, Y. L. L., Korol, V., Lamberts, A., Kupfer, T., Breivik, K., Ludwig, B., &#38; Drout, M. R. (2020). Stars stripped in binaries: The living gravitational-wave sources. <i>The Astrophysical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-4357/abbda5\">https://doi.org/10.3847/1538-4357/abbda5</a>","ista":"Götberg YLL, Korol V, Lamberts A, Kupfer T, Breivik K, Ludwig B, Drout MR. 2020. Stars stripped in binaries: The living gravitational-wave sources. The Astrophysical Journal. 904(1), 56.","mla":"Götberg, Ylva Louise Linsdotter, et al. “Stars Stripped in Binaries: The Living Gravitational-Wave Sources.” <i>The Astrophysical Journal</i>, vol. 904, no. 1, 56, American Astronomical Society, 2020, doi:<a href=\"https://doi.org/10.3847/1538-4357/abbda5\">10.3847/1538-4357/abbda5</a>.","ama":"Götberg YLL, Korol V, Lamberts A, et al. Stars stripped in binaries: The living gravitational-wave sources. <i>The Astrophysical Journal</i>. 2020;904(1). doi:<a href=\"https://doi.org/10.3847/1538-4357/abbda5\">10.3847/1538-4357/abbda5</a>"},"oa":1,"publication_status":"published","date_published":"2020-11-20T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://doi.org/10.48550/arXiv.2006.07382"}]},{"publication_identifier":{"eissn":["1538-4357"],"issn":["0004-637X"]},"doi":"10.3847/1538-4357/abaefa","quality_controlled":"1","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"issue":"1","language":[{"iso":"eng"}],"author":[{"last_name":"Secunda","first_name":"Amy","full_name":"Secunda, Amy"},{"last_name":"Cen","first_name":"Renyue","full_name":"Cen, Renyue"},{"full_name":"Kimm, Taysun","first_name":"Taysun","last_name":"Kimm"},{"full_name":"Götberg, Ylva Louise Linsdotter","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911","first_name":"Ylva Louise Linsdotter","last_name":"Götberg"},{"full_name":"de Mink, Selma E.","last_name":"de Mink","first_name":"Selma E."}],"day":"23","article_number":"72","arxiv":1,"title":"Delayed photons from binary evolution help reionize the universe","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publisher":"American Astronomical Society","publication":"The Astrophysical Journal","article_type":"original","article_processing_charge":"No","scopus_import":"1","publication_status":"published","oa":1,"date_published":"2020-09-23T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://doi.org/10.3847/1538-4357/abaefa"}],"external_id":{"arxiv":["2007.15012"]},"status":"public","extern":"1","intvolume":"       901","citation":{"short":"A. Secunda, R. Cen, T. Kimm, Y.L.L. Götberg, S.E. de Mink, The Astrophysical Journal 901 (2020).","ieee":"A. Secunda, R. Cen, T. Kimm, Y. L. L. Götberg, and S. E. de Mink, “Delayed photons from binary evolution help reionize the universe,” <i>The Astrophysical Journal</i>, vol. 901, no. 1. American Astronomical Society, 2020.","chicago":"Secunda, Amy, Renyue Cen, Taysun Kimm, Ylva Louise Linsdotter Götberg, and Selma E. de Mink. “Delayed Photons from Binary Evolution Help Reionize the Universe.” <i>The Astrophysical Journal</i>. American Astronomical Society, 2020. <a href=\"https://doi.org/10.3847/1538-4357/abaefa\">https://doi.org/10.3847/1538-4357/abaefa</a>.","ista":"Secunda A, Cen R, Kimm T, Götberg YLL, de Mink SE. 2020. Delayed photons from binary evolution help reionize the universe. The Astrophysical Journal. 901(1), 72.","mla":"Secunda, Amy, et al. “Delayed Photons from Binary Evolution Help Reionize the Universe.” <i>The Astrophysical Journal</i>, vol. 901, no. 1, 72, American Astronomical Society, 2020, doi:<a href=\"https://doi.org/10.3847/1538-4357/abaefa\">10.3847/1538-4357/abaefa</a>.","apa":"Secunda, A., Cen, R., Kimm, T., Götberg, Y. L. L., &#38; de Mink, S. E. (2020). Delayed photons from binary evolution help reionize the universe. <i>The Astrophysical Journal</i>. American Astronomical Society. <a href=\"https://doi.org/10.3847/1538-4357/abaefa\">https://doi.org/10.3847/1538-4357/abaefa</a>","ama":"Secunda A, Cen R, Kimm T, Götberg YLL, de Mink SE. Delayed photons from binary evolution help reionize the universe. <i>The Astrophysical Journal</i>. 2020;901(1). doi:<a href=\"https://doi.org/10.3847/1538-4357/abaefa\">10.3847/1538-4357/abaefa</a>"},"type":"journal_article","month":"09","oa_version":"Published Version","abstract":[{"lang":"eng","text":"High-resolution numerical simulations including feedback and aimed at calculating the escape fraction (fesc) of hydrogen-ionizing photons often assume stellar radiation based on single-stellar population synthesis models. However, strong evidence suggests the binary fraction of massive stars is ≳70%. Moreover, simulations so far have yielded values of fesc falling only on the lower end of the ∼10%–20% range, the amount presumed necessary to reionize the universe. Analyzing a high-resolution (4 pc) cosmological radiation-hydrodynamic simulation, we study how fesc changes when we include two different products of binary stellar evolution—stars stripped of their hydrogen envelopes and massive blue stragglers. Both produce significant amounts of ionizing photons 10–200 Myr after each starburst. We find the relative importance of these photons to be amplified with respect to escaped ionizing photons, because peaks in star formation rates (SFRs) and fesc are often out of phase by this 10–200 Myr. Additionally, low-mass, bursty galaxies emit Lyman continuum radiation primarily from binary products when SFRs are low. Observations of these galaxies by the James Webb Space Telescope could provide crucial information on the evolution of binary stars as a function of redshift. Overall, including stripped stars and massive blue stragglers increases our photon-weighted mean escape fraction ($\\langle {f}_{\\mathrm{esc}}\\rangle $) by ∼13% and ∼10%, respectively, resulting in $\\langle {f}_{\\mathrm{esc}}\\rangle =17 \\% $. Our results emphasize that using updated stellar population synthesis models with binary stellar evolution provides a more sound physical basis for stellar reionization."}],"date_updated":"2023-08-09T13:01:45Z","volume":901,"date_created":"2023-08-03T10:12:16Z","year":"2020","_id":"13461"},{"publication":"Astronomy & Astrophysics","article_type":"original","article_processing_charge":"No","scopus_import":"1","publisher":"EDP Sciences","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_number":"A56","title":"Predictions for the hydrogen-free ejecta of pulsational pair-instability supernovae","arxiv":1,"author":[{"last_name":"Renzo","first_name":"M.","full_name":"Renzo, M."},{"last_name":"Farmer","first_name":"R.","full_name":"Farmer, R."},{"first_name":"S.","last_name":"Justham","full_name":"Justham, S."},{"first_name":"Ylva Louise Linsdotter","last_name":"Götberg","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","orcid":"0000-0002-6960-6911","full_name":"Götberg, Ylva Louise Linsdotter"},{"first_name":"S. E.","last_name":"de Mink","full_name":"de Mink, S. E."},{"last_name":"Zapartas","first_name":"E.","full_name":"Zapartas, E."},{"full_name":"Marchant, P.","last_name":"Marchant","first_name":"P."},{"first_name":"N.","last_name":"Smith","full_name":"Smith, N."}],"day":"12","keyword":["Space and Planetary Science","Astronomy and Astrophysics"],"language":[{"iso":"eng"}],"doi":"10.1051/0004-6361/202037710","quality_controlled":"1","publication_identifier":{"issn":["0004-6361"],"eissn":["1432-0746"]},"_id":"13463","year":"2020","volume":640,"date_created":"2023-08-03T10:12:58Z","month":"08","type":"journal_article","oa_version":"Published Version","abstract":[{"lang":"eng","text":"Present and upcoming time-domain astronomy efforts, in part driven by gravitational-wave follow-up campaigns, will unveil a variety of rare explosive transients in the sky. Here, we focus on pulsational pair-instability evolution, which can result in signatures that are observable with electromagnetic and gravitational waves. We simulated grids of bare helium stars to characterize the resulting black hole (BH) masses together with the ejecta composition, velocity, and thermal state. We find that the stars do not react “elastically” to the thermonuclear ignition in the core: there is not a one-to-one correspondence between pair-instability driven ignition and mass ejections, which causes ambiguity as to what is an observable pulse. In agreement with previous studies, we find that for initial helium core masses of 37.5 M⊙ ≲ MHe, init ≲ 41 M⊙, corresponding to carbon-oxygen core masses 27.5 M⊙ ≲ MCO ≲ 30.1 M⊙, the explosions are not strong enough to affect the surface. With increasing initial helium core mass, they become progressively stronger causing first large radial expansion (41 M⊙ ≲ MHe, init ≲ 42 M⊙, corresponding to 30.1 M⊙ ≲ MCO ≲ 30.8 M⊙) and, finally, also mass ejection episodes (for MHe, init ≳ 42 M⊙, or MCO ≳ 30.8 M⊙). The lowest mass helium core to be fully disrupted in a pair-instability supernova is MHe, init ≃ 80 M⊙, corresponding to MCO ≃ 55 M⊙. Models with MHe, init ≳ 200 M⊙ (MCO ≳ 114 M⊙) reach the photodisintegration regime, resulting in BHs with masses of MBH ≳ 125 M⊙. Although this is currently considered unlikely, if BHs from these models form via (weak) explosions, the previously-ejected material might be hit by the blast wave and convert kinetic energy into observable electromagnetic radiation. We characterize the hydrogen-free circumstellar material from the pulsational pair-instability of helium cores by simply assuming that the ejecta maintain a constant velocity after ejection. We find that our models produce helium-rich ejecta with mass of 10−3 M⊙ ≲ MCSM ≲ 40 M⊙, the larger values corresponding to the more massive progenitor stars. These ejecta are typically launched at a few thousand km s−1 and reach distances of ∼1012 − 1015 cm before the core-collapse of the star. The delays between mass ejection events and the final collapse span a wide and mass-dependent range (from subhour to 104 years), and the shells ejected can also collide with each other, powering supernova impostor events before the final core-collapse. The range of properties we find suggests a possible connection with (some) type Ibn supernovae."}],"date_updated":"2023-08-09T12:58:41Z","intvolume":"       640","extern":"1","citation":{"short":"M. Renzo, R. Farmer, S. Justham, Y.L.L. Götberg, S.E. de Mink, E. Zapartas, P. Marchant, N. Smith, Astronomy &#38; Astrophysics 640 (2020).","chicago":"Renzo, M., R. Farmer, S. Justham, Ylva Louise Linsdotter Götberg, S. E. de Mink, E. Zapartas, P. Marchant, and N. Smith. “Predictions for the Hydrogen-Free Ejecta of Pulsational Pair-Instability Supernovae.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2020. <a href=\"https://doi.org/10.1051/0004-6361/202037710\">https://doi.org/10.1051/0004-6361/202037710</a>.","ieee":"M. Renzo <i>et al.</i>, “Predictions for the hydrogen-free ejecta of pulsational pair-instability supernovae,” <i>Astronomy &#38; Astrophysics</i>, vol. 640. EDP Sciences, 2020.","apa":"Renzo, M., Farmer, R., Justham, S., Götberg, Y. L. L., de Mink, S. E., Zapartas, E., … Smith, N. (2020). Predictions for the hydrogen-free ejecta of pulsational pair-instability supernovae. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202037710\">https://doi.org/10.1051/0004-6361/202037710</a>","ista":"Renzo M, Farmer R, Justham S, Götberg YLL, de Mink SE, Zapartas E, Marchant P, Smith N. 2020. Predictions for the hydrogen-free ejecta of pulsational pair-instability supernovae. Astronomy &#38; Astrophysics. 640, A56.","mla":"Renzo, M., et al. “Predictions for the Hydrogen-Free Ejecta of Pulsational Pair-Instability Supernovae.” <i>Astronomy &#38; Astrophysics</i>, vol. 640, A56, EDP Sciences, 2020, doi:<a href=\"https://doi.org/10.1051/0004-6361/202037710\">10.1051/0004-6361/202037710</a>.","ama":"Renzo M, Farmer R, Justham S, et al. Predictions for the hydrogen-free ejecta of pulsational pair-instability supernovae. <i>Astronomy &#38; Astrophysics</i>. 2020;640. doi:<a href=\"https://doi.org/10.1051/0004-6361/202037710\">10.1051/0004-6361/202037710</a>"},"external_id":{"arxiv":["2002.05077"]},"status":"public","date_published":"2020-08-12T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://doi.org/10.1051/0004-6361/202037710"}],"publication_status":"published","oa":1},{"date_created":"2023-08-03T10:13:10Z","volume":637,"abstract":[{"text":"Massive binaries that merge as compact objects are the progenitors of gravitational-wave sources. Most of these binaries experience one or more phases of mass transfer, during which one of the stars loses all or part of its outer envelope and becomes a stripped-envelope star. The evolution of the size of these stripped stars is crucial in determining whether they experience further interactions and understanding their ultimate fate. We present new calculations of stripped-envelope stars based on binary evolution models computed with MESA. We use these to investigate their radius evolution as a function of mass and metallicity. We further discuss their pre-supernova observable characteristics and potential consequences of their evolution on the properties of supernovae from stripped stars. At high metallicity, we find that practically all of the hydrogen-rich envelope is removed, which is in agreement with earlier findings. Only progenitors with initial masses below 10 M⊙ expand to large radii (up to 100 R⊙), while more massive progenitors remain compact. At low metallicity, a substantial amount of hydrogen remains and the progenitors can, in principle, expand to giant sizes (> 400 R⊙) for all masses we consider. This implies that they can fill their Roche lobe anew. We show that the prescriptions commonly used in population synthesis models underestimate the stellar radii by up to two orders of magnitude. We expect that this has consequences for the predictions for gravitational-wave sources from double neutron star mergers, particularly with regard to their metallicity dependence.","lang":"eng"}],"date_updated":"2023-08-09T12:56:32Z","month":"05","oa_version":"Published Version","type":"journal_article","_id":"13464","year":"2020","main_file_link":[{"open_access":"1","url":"https://doi.org/10.1051/0004-6361/201937300"}],"date_published":"2020-05-01T00:00:00Z","oa":1,"publication_status":"published","citation":{"mla":"Laplace, E., et al. “The Expansion of Stripped-Envelope Stars: Consequences for Supernovae and Gravitational-Wave Progenitors.” <i>Astronomy &#38; Astrophysics</i>, vol. 637, A6, EDP Sciences, 2020, doi:<a href=\"https://doi.org/10.1051/0004-6361/201937300\">10.1051/0004-6361/201937300</a>.","ista":"Laplace E, Götberg YLL, de Mink SE, Justham S, Farmer R. 2020. The expansion of stripped-envelope stars: Consequences for supernovae and gravitational-wave progenitors. Astronomy &#38; Astrophysics. 637, A6.","apa":"Laplace, E., Götberg, Y. L. L., de Mink, S. E., Justham, S., &#38; Farmer, R. (2020). The expansion of stripped-envelope stars: Consequences for supernovae and gravitational-wave progenitors. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/201937300\">https://doi.org/10.1051/0004-6361/201937300</a>","ama":"Laplace E, Götberg YLL, de Mink SE, Justham S, Farmer R. The expansion of stripped-envelope stars: Consequences for supernovae and gravitational-wave progenitors. <i>Astronomy &#38; Astrophysics</i>. 2020;637. doi:<a href=\"https://doi.org/10.1051/0004-6361/201937300\">10.1051/0004-6361/201937300</a>","short":"E. Laplace, Y.L.L. Götberg, S.E. de Mink, S. Justham, R. Farmer, Astronomy &#38; Astrophysics 637 (2020).","ieee":"E. Laplace, Y. L. L. Götberg, S. E. de Mink, S. Justham, and R. Farmer, “The expansion of stripped-envelope stars: Consequences for supernovae and gravitational-wave progenitors,” <i>Astronomy &#38; Astrophysics</i>, vol. 637. EDP Sciences, 2020.","chicago":"Laplace, E., Ylva Louise Linsdotter Götberg, S. E. de Mink, S. Justham, and R. Farmer. “The Expansion of Stripped-Envelope Stars: Consequences for Supernovae and Gravitational-Wave Progenitors.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2020. <a href=\"https://doi.org/10.1051/0004-6361/201937300\">https://doi.org/10.1051/0004-6361/201937300</a>."},"extern":"1","intvolume":"       637","external_id":{"arxiv":["2003.01120"]},"status":"public","title":"The expansion of stripped-envelope stars: Consequences for supernovae and gravitational-wave progenitors","arxiv":1,"article_number":"A6","day":"01","author":[{"full_name":"Laplace, E.","last_name":"Laplace","first_name":"E."},{"full_name":"Götberg, Ylva Louise Linsdotter","orcid":"0000-0002-6960-6911","id":"d0648d0c-0f64-11ee-a2e0-dd0faa2e4f7d","last_name":"Götberg","first_name":"Ylva Louise Linsdotter"},{"last_name":"de Mink","first_name":"S. E.","full_name":"de Mink, S. E."},{"full_name":"Justham, S.","first_name":"S.","last_name":"Justham"},{"last_name":"Farmer","first_name":"R.","full_name":"Farmer, R."}],"scopus_import":"1","article_processing_charge":"No","article_type":"original","publication":"Astronomy & Astrophysics","publisher":"EDP Sciences","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","quality_controlled":"1","doi":"10.1051/0004-6361/201937300","publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"language":[{"iso":"eng"}],"keyword":["Space and Planetary Science","Astronomy and Astrophysics"]}]