---
_id: '11501'
abstract:
- lang: eng
text: We investigated the ultraviolet (UV) spectral properties of faint Lyman-α
emitters (LAEs) in the redshift range 2.9 ≤ z ≤ 4.6, and we provide material to
prepare future observations of the faint Universe. We used data from the MUSE
Hubble Ultra Deep Survey to construct mean rest-frame spectra of continuum-faint
(median MUV of −18 and down to MUV of −16), low stellar mass (median value of
108.4 M⊙ and down to 107 M⊙) LAEs at redshift z ≳ 3. We computed various averaged
spectra of LAEs, subsampled on the basis of their observational (e.g., Lyα strength,
UV magnitude and spectral slope) and physical (e.g., stellar mass and star-formation
rate) properties. We searched for UV spectral features other than Lyα, such as
higher ionization nebular emission lines and absorption features. We successfully
observed the O III]λ1666 and [C III]λ1907+C III]λ1909 collisionally excited emission
lines and the He IIλ1640 recombination feature, as well as the resonant C IVλλ1548,1551
doublet either in emission or P-Cygni. We compared the observed spectral properties
of the different mean spectra and find the emission lines to vary with the observational
and physical properties of the LAEs. In particular, the mean spectra of LAEs with
larger Lyα equivalent widths, fainter UV magnitudes, bluer UV spectral slopes,
and lower stellar masses show the strongest nebular emission. The line ratios
of these lines are similar to those measured in the spectra of local metal-poor
galaxies, while their equivalent widths are weaker compared to the handful of
extreme values detected in individual spectra of z > 2 galaxies. This suggests
that weak UV features are likely ubiquitous in high z, low-mass, and faint LAEs.
We publicly released the stacked spectra, as they can serve as empirical templates
for the design of future observations, such as those with the James Webb Space
Telescope and the Extremely Large Telescope.
acknowledgement: 'We thank Margherita Talia, Stéphane Charlot, Adele Plat and Alba
Vidal-García for helpful discussions. This work is supported by the ERC advanced
grant 339659-MUSICOS (R. Bacon). AF acknowledges the support from grant PRIN MIUR
2017 20173ML3WW. MVM and JP would like to thank the Leiden/ESA Astrophysics Program
for Summer Students (LEAPS) for funding at the outset of this project. FL, HK, and
AV acknowledge support from the ERC starting grant ERC-757258-TRIPLE. TH was supported
by Leading Initiative for Excellent Young Researchers, MEXT, Japan. JB acknowledges
support by FCT/MCTES through national funds by the grant UID/FIS/04434/2019, UIDB/04434/2020
and UIDP/04434/2020 and through the Investigador FCT Contract No. IF/01654/2014/CP1215/CT0003.
HI acknowledges support from JSPS KAKENHI Grant Number JP19K23462. We would also
like to thank the organizers and participants of the Leiden Lorentz Center workshop:
Revolutionary Spectroscopy of Today as a Springboard to Webb. This work made use
of several open source python packages: NUMPY (van der Walt et al. 2011), MATPLOTLIB
(Hunter 2007), ASTROPY (Astropy Collaboration 2013) and MPDAF (MUSE Python Data
Analysis Framework, Piqueras et al. 2019).'
article_number: A118
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Anna
full_name: Feltre, Anna
last_name: Feltre
- first_name: Michael V.
full_name: Maseda, Michael V.
last_name: Maseda
- first_name: Roland
full_name: Bacon, Roland
last_name: Bacon
- first_name: Jayadev
full_name: Pradeep, Jayadev
last_name: Pradeep
- first_name: Floriane
full_name: Leclercq, Floriane
last_name: Leclercq
- first_name: Haruka
full_name: Kusakabe, Haruka
last_name: Kusakabe
- first_name: Lutz
full_name: Wisotzki, Lutz
last_name: Wisotzki
- first_name: Takuya
full_name: Hashimoto, Takuya
last_name: Hashimoto
- first_name: Kasper B.
full_name: Schmidt, Kasper B.
last_name: Schmidt
- first_name: Jeremy
full_name: Blaizot, Jeremy
last_name: Blaizot
- first_name: Jarle
full_name: Brinchmann, Jarle
last_name: Brinchmann
- first_name: Leindert
full_name: Boogaard, Leindert
last_name: Boogaard
- first_name: Sebastiano
full_name: Cantalupo, Sebastiano
last_name: Cantalupo
- first_name: David
full_name: Carton, David
last_name: Carton
- first_name: Hanae
full_name: Inami, Hanae
last_name: Inami
- first_name: Wolfram
full_name: Kollatschny, Wolfram
last_name: Kollatschny
- first_name: Raffaella A.
full_name: Marino, Raffaella A.
last_name: Marino
- first_name: Jorryt J
full_name: Matthee, Jorryt J
id: 7439a258-f3c0-11ec-9501-9df22fe06720
last_name: Matthee
orcid: 0000-0003-2871-127X
- first_name: Themiya
full_name: Nanayakkara, Themiya
last_name: Nanayakkara
- first_name: Johan
full_name: Richard, Johan
last_name: Richard
- first_name: Joop
full_name: Schaye, Joop
last_name: Schaye
- first_name: Laurence
full_name: Tresse, Laurence
last_name: Tresse
- first_name: Tanya
full_name: Urrutia, Tanya
last_name: Urrutia
- first_name: Anne
full_name: Verhamme, Anne
last_name: Verhamme
- first_name: Peter M.
full_name: Weilbacher, Peter M.
last_name: Weilbacher
citation:
ama: 'Feltre A, Maseda MV, Bacon R, et al. The MUSE Hubble Ultra Deep Field Survey:
XV. The mean rest-UV spectra of Lyα emitters at z > 3. Astronomy &
Astrophysics. 2020;641. doi:10.1051/0004-6361/202038133'
apa: 'Feltre, A., Maseda, M. V., Bacon, R., Pradeep, J., Leclercq, F., Kusakabe,
H., … Weilbacher, P. M. (2020). The MUSE Hubble Ultra Deep Field Survey: XV. The
mean rest-UV spectra of Lyα emitters at z > 3. Astronomy & Astrophysics.
EDP Sciences. https://doi.org/10.1051/0004-6361/202038133'
chicago: 'Feltre, Anna, Michael V. Maseda, Roland Bacon, Jayadev Pradeep, Floriane
Leclercq, Haruka Kusakabe, Lutz Wisotzki, et al. “The MUSE Hubble Ultra Deep Field
Survey: XV. The Mean Rest-UV Spectra of Lyα Emitters at z > 3.” Astronomy
& Astrophysics. EDP Sciences, 2020. https://doi.org/10.1051/0004-6361/202038133.'
ieee: 'A. Feltre et al., “The MUSE Hubble Ultra Deep Field Survey: XV. The
mean rest-UV spectra of Lyα emitters at z > 3,” Astronomy & Astrophysics,
vol. 641. EDP Sciences, 2020.'
ista: 'Feltre A, Maseda MV, Bacon R, Pradeep J, Leclercq F, Kusakabe H, Wisotzki
L, Hashimoto T, Schmidt KB, Blaizot J, Brinchmann J, Boogaard L, Cantalupo S,
Carton D, Inami H, Kollatschny W, Marino RA, Matthee JJ, Nanayakkara T, Richard
J, Schaye J, Tresse L, Urrutia T, Verhamme A, Weilbacher PM. 2020. The MUSE Hubble
Ultra Deep Field Survey: XV. The mean rest-UV spectra of Lyα emitters at z >
3. Astronomy & Astrophysics. 641, A118.'
mla: 'Feltre, Anna, et al. “The MUSE Hubble Ultra Deep Field Survey: XV. The Mean
Rest-UV Spectra of Lyα Emitters at z > 3.” Astronomy & Astrophysics,
vol. 641, A118, EDP Sciences, 2020, doi:10.1051/0004-6361/202038133.'
short: A. Feltre, M.V. Maseda, R. Bacon, J. Pradeep, F. Leclercq, H. Kusakabe, L.
Wisotzki, T. Hashimoto, K.B. Schmidt, J. Blaizot, J. Brinchmann, L. Boogaard,
S. Cantalupo, D. Carton, H. Inami, W. Kollatschny, R.A. Marino, J.J. Matthee,
T. Nanayakkara, J. Richard, J. Schaye, L. Tresse, T. Urrutia, A. Verhamme, P.M.
Weilbacher, Astronomy & Astrophysics 641 (2020).
date_created: 2022-07-06T09:38:16Z
date_published: 2020-09-18T00:00:00Z
date_updated: 2022-07-19T09:35:43Z
day: '18'
doi: 10.1051/0004-6361/202038133
extern: '1'
external_id:
arxiv:
- '2007.01878'
intvolume: ' 641'
keyword:
- Space and Planetary Science
- Astronomy and Astrophysics
- 'galaxies: evolution / galaxies: high-redshift / ISM: lines and bands / ultraviolet:
ISM / ultraviolet: galaxies'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2007.01878
month: '09'
oa: 1
oa_version: Published Version
publication: Astronomy & Astrophysics
publication_identifier:
eissn:
- 1432-0746
issn:
- 0004-6361
publication_status: published
publisher: EDP Sciences
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'The MUSE Hubble Ultra Deep Field Survey: XV. The mean rest-UV spectra of Lyα
emitters at z > 3'
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 641
year: '2020'
...
---
_id: '11503'
abstract:
- lang: eng
text: "Context. The Lyα emitter (LAE) fraction, XLAE, is a potentially powerful
probe of the evolution of the intergalactic neutral hydrogen gas fraction. However,
uncertainties in the measurement of XLAE are still under debate.\r\nAims. Thanks
to deep data obtained with the integral field spectrograph Multi Unit Spectroscopic
Explorer (MUSE), we can measure the evolution of the LAE fraction homogeneously
over a wide redshift range of z ≈ 3–6 for UV-faint galaxies (down to UV magnitudes
of M1500 ≈ −17.75). This is a significantly fainter range than in former studies
(M1500 ≤ −18.75) and it allows us to probe the bulk of the population of high-redshift
star-forming galaxies.\r\nMethods. We constructed a UV-complete photometric-redshift
sample following UV luminosity functions and measured the Lyα emission with MUSE
using the latest (second) data release from the MUSE Hubble Ultra Deep Field Survey.\r\nResults.
We derived the redshift evolution of XLAE for M1500 ∈ [ − 21.75; −17.75] for the
first time with a equivalent width range EW(Lyα) ≥ 65 Å and found low values of
XLAE ≲ 30% at z ≲ 6. The best-fit linear relation is XLAE = 0.07+0.06−0.03z −
0.22+0.12−0.24. For M1500 ∈ [ − 20.25; −18.75] and EW(Lyα) ≥ 25 Å, our XLAE values
are consistent with those in the literature within 1σ at z ≲ 5, but our median
values are systematically lower than reported values over the whole redshift range.
In addition, we do not find a significant dependence of XLAE on M1500 for EW(Lyα)
≥ 50 Å at z ≈ 3–4, in contrast with previous work. The differences in XLAE mainly
arise from selection biases for Lyman Break Galaxies (LBGs) in the literature:
UV-faint LBGs are more easily selected if they have strong Lyα emission, hence
XLAE is biased towards higher values when those samples are used.\r\nConclusions.
Our results suggest either a lower increase of XLAE towards z ≈ 6 than previously
suggested, or even a turnover of XLAE at z ≈ 5.5, which may be the signature of
a late or patchy reionization process. We compared our results with predictions
from a cosmological galaxy evolution model. We find that a model with a bursty
star formation (SF) can reproduce our observed LAE fractions much better than
models where SF is a smooth function of time."
acknowledgement: We thank the anonymous referee for constructive comments and suggestions.
We would like to express our gratitude to Stephane De Barros and Pablo Arrabal Haro
for kindly providing their data plotted in Figs. 1, 2, and 8. We are grateful to
Kazuhiro Shimasaku, Masami Ouchi, Rieko Momose, Daniel Schaerer, Hidenobu Yajima,
Taku Okamura, Makoto Ando, and Hinako Goto for giving insightful comments and suggestions.
This work is based on observations taken by VLT, which is operated by European Southern
Observatory. This research made use of Astropy (http://www.astropy.org), which is
a community-developed core Python package for Astronomy (Astropy Collaboration 2013,
2018), MARZ, MPDAF, and matplotlib (Hunter 2007). H.K. acknowledges support from
Japan Society for the Promotion of Science (JSPS) through the JSPS Research Fellowship
for Young Scientists and Overseas Challenge Program for Young Researchers. AV acknowledges
support from the ERC starting grant 757258-TRIPLE and the SNF Professorship 176808-TRIPLE.
This work was supported by the project FOGHAR (Agence Nationale de la Recherche,
ANR-13-BS05-0010-02). JB acknowledges support from the ORAGE project from the Agence
Nationale de la Recherche under grant ANR-14-CE33-0016-03. JR acknowledges support
from the ERC starting grant 336736-CALENDS. T. H. acknowledges supports by the Grant-inAid
for Scientic Research 19J01620.
article_number: A12
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Haruka
full_name: Kusakabe, Haruka
last_name: Kusakabe
- first_name: Jérémy
full_name: Blaizot, Jérémy
last_name: Blaizot
- first_name: Thibault
full_name: Garel, Thibault
last_name: Garel
- first_name: Anne
full_name: Verhamme, Anne
last_name: Verhamme
- first_name: Roland
full_name: Bacon, Roland
last_name: Bacon
- first_name: Johan
full_name: Richard, Johan
last_name: Richard
- first_name: Takuya
full_name: Hashimoto, Takuya
last_name: Hashimoto
- first_name: Hanae
full_name: Inami, Hanae
last_name: Inami
- first_name: Simon
full_name: Conseil, Simon
last_name: Conseil
- first_name: Bruno
full_name: Guiderdoni, Bruno
last_name: Guiderdoni
- first_name: Alyssa B.
full_name: Drake, Alyssa B.
last_name: Drake
- first_name: Edmund
full_name: Christian Herenz, Edmund
last_name: Christian Herenz
- first_name: Joop
full_name: Schaye, Joop
last_name: Schaye
- first_name: Pascal
full_name: Oesch, Pascal
last_name: Oesch
- first_name: Jorryt J
full_name: Matthee, Jorryt J
id: 7439a258-f3c0-11ec-9501-9df22fe06720
last_name: Matthee
orcid: 0000-0003-2871-127X
- first_name: Raffaella
full_name: Anna Marino, Raffaella
last_name: Anna Marino
- first_name: Kasper
full_name: Borello Schmidt, Kasper
last_name: Borello Schmidt
- first_name: Roser
full_name: Pelló, Roser
last_name: Pelló
- first_name: Michael
full_name: Maseda, Michael
last_name: Maseda
- first_name: Floriane
full_name: Leclercq, Floriane
last_name: Leclercq
- first_name: Josephine
full_name: Kerutt, Josephine
last_name: Kerutt
- first_name: Guillaume
full_name: Mahler, Guillaume
last_name: Mahler
citation:
ama: 'Kusakabe H, Blaizot J, Garel T, et al. The MUSE Hubble Ultra Deep Field Survey:
XIV. Evolution of the Lyα emitter fraction from z = 3 to z = 6. Astronomy &
Astrophysics. 2020;638. doi:10.1051/0004-6361/201937340'
apa: 'Kusakabe, H., Blaizot, J., Garel, T., Verhamme, A., Bacon, R., Richard, J.,
… Mahler, G. (2020). The MUSE Hubble Ultra Deep Field Survey: XIV. Evolution of
the Lyα emitter fraction from z = 3 to z = 6. Astronomy & Astrophysics.
EDP Sciences. https://doi.org/10.1051/0004-6361/201937340'
chicago: 'Kusakabe, Haruka, Jérémy Blaizot, Thibault Garel, Anne Verhamme, Roland
Bacon, Johan Richard, Takuya Hashimoto, et al. “The MUSE Hubble Ultra Deep Field
Survey: XIV. Evolution of the Lyα Emitter Fraction from z = 3 to z = 6.” Astronomy
& Astrophysics. EDP Sciences, 2020. https://doi.org/10.1051/0004-6361/201937340.'
ieee: 'H. Kusakabe et al., “The MUSE Hubble Ultra Deep Field Survey: XIV.
Evolution of the Lyα emitter fraction from z = 3 to z = 6,” Astronomy &
Astrophysics, vol. 638. EDP Sciences, 2020.'
ista: 'Kusakabe H, Blaizot J, Garel T, Verhamme A, Bacon R, Richard J, Hashimoto
T, Inami H, Conseil S, Guiderdoni B, Drake AB, Christian Herenz E, Schaye J, Oesch
P, Matthee JJ, Anna Marino R, Borello Schmidt K, Pelló R, Maseda M, Leclercq F,
Kerutt J, Mahler G. 2020. The MUSE Hubble Ultra Deep Field Survey: XIV. Evolution
of the Lyα emitter fraction from z = 3 to z = 6. Astronomy & Astrophysics.
638, A12.'
mla: 'Kusakabe, Haruka, et al. “The MUSE Hubble Ultra Deep Field Survey: XIV. Evolution
of the Lyα Emitter Fraction from z = 3 to z = 6.” Astronomy & Astrophysics,
vol. 638, A12, EDP Sciences, 2020, doi:10.1051/0004-6361/201937340.'
short: H. Kusakabe, J. Blaizot, T. Garel, A. Verhamme, R. Bacon, J. Richard, T.
Hashimoto, H. Inami, S. Conseil, B. Guiderdoni, A.B. Drake, E. Christian Herenz,
J. Schaye, P. Oesch, J.J. Matthee, R. Anna Marino, K. Borello Schmidt, R. Pelló,
M. Maseda, F. Leclercq, J. Kerutt, G. Mahler, Astronomy & Astrophysics 638
(2020).
date_created: 2022-07-06T09:50:48Z
date_published: 2020-06-03T00:00:00Z
date_updated: 2022-07-19T09:35:20Z
day: '03'
doi: 10.1051/0004-6361/201937340
extern: '1'
external_id:
arxiv:
- '2003.12083'
intvolume: ' 638'
keyword:
- Space and Planetary Science
- Astronomy and Astrophysics
- 'dark ages / reionization / first stars / early Universe / cosmology: observations
/ galaxies: evolution / galaxies: high-redshift / intergalactic medium'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2003.12083
month: '06'
oa: 1
oa_version: Published Version
publication: Astronomy & Astrophysics
publication_identifier:
eissn:
- 1432-0746
issn:
- 0004-6361
publication_status: published
publisher: EDP Sciences
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'The MUSE Hubble Ultra Deep Field Survey: XIV. Evolution of the Lyα emitter
fraction from z = 3 to z = 6'
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 638
year: '2020'
...
---
_id: '11499'
abstract:
- lang: eng
text: Deep optical spectroscopic surveys of galaxies provide a unique opportunity
to investigate rest-frame ultra-violet (UV) emission line properties of galaxies
at z ∼ 2 − 4.5. Here we combine VLT/MUSE Guaranteed Time Observations of the Hubble
Deep Field South, Ultra Deep Field, COSMOS, and several quasar fields with other
publicly available data from VLT/VIMOS and VLT/FORS2 to construct a catalogue
of He II λ1640 emitters at z ≳ 2. The deepest areas of our MUSE pointings reach
a 3σ line flux limit of 3.1 × 10−19 erg s−1 cm−2. After discarding broad-line
active galactic nuclei, we find 13 He II λ1640 detections from MUSE with a median
MUV = −20.1 and 21 tentative He II λ1640 detections from other public surveys.
Excluding Lyα, all except two galaxies in our sample show at least one other rest-UV
emission line, with C III] λ1907, λ1909 being the most prominent. We use multi-wavelength
data available in the Hubble legacy fields to derive basic galaxy properties of
our sample through spectral energy distribution fitting techniques. Taking advantage
of the high-quality spectra obtained by MUSE (∼10 − 30 h of exposure time per
pointing), we use photo-ionisation models to study the rest-UV emission line diagnostics
of the He II λ1640 emitters. Line ratios of our sample can be reproduced by moderately
sub-solar photo-ionisation models, however, we find that including effects of
binary stars lead to degeneracies in most free parameters. Even after considering
extra ionising photons produced by extreme sub-solar metallicity binary stellar
models, photo-ionisation models are unable to reproduce rest-frame He II λ1640
equivalent widths (∼0.2 − 10 Å), thus additional mechanisms are necessary in models
to match the observed He II λ1640 properties.
acknowledgement: 'The authors wish to thank the referee for constructive comments
that improved the paper substantially. We thank the BPASS team for making the stellar
population models available. We thank Elizabeth Stanway, Claus Leitherer, Daniel
Schaerer, Jorick Vink, and Nell Byler for insightful discussions. We thank the Lorentz
Centre and the scientific organizers of the Characterizing galaxies with spectroscopy
with a view for JWST workshop held at the Lorentz Centre in 2017 October, which
promoted useful discussions in the wider community. TN, JB, and RB acknowledges
the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) top grant TOP1.16.057.
AF acknowledges support from the ERC via an Advanced Grant under grant agreement
no. 339659-MUSICOS. JB acknowledges support by Fundação para a Ciência e a Tecnologia
(FCT) through national funds (UID/FIS/04434/2013) and Investigador FCT contract
IF/01654/2014/CP1215/CT0003, and by FEDER through COMPETE2020 (POCI-01-0145-FEDER-007672).
JR acknowledges support from the ERC Starting grant 336736 (CALENDS). This research
made use of astropy (http://www.astropy.org) a community-developed core Python package
for Astronomy (Astropy Collaboration 2013, 2018) and pandas (McKinney 2010). Figures
were generated using matplotlib (Hunter 2007) and seaborn (https://seaborn.pydata.org).
Facilities: VLT (MUSE).'
article_number: A89
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Themiya
full_name: Nanayakkara, Themiya
last_name: Nanayakkara
- first_name: Jarle
full_name: Brinchmann, Jarle
last_name: Brinchmann
- first_name: Leindert
full_name: Boogaard, Leindert
last_name: Boogaard
- first_name: Rychard
full_name: Bouwens, Rychard
last_name: Bouwens
- first_name: Sebastiano
full_name: Cantalupo, Sebastiano
last_name: Cantalupo
- first_name: Anna
full_name: Feltre, Anna
last_name: Feltre
- first_name: Wolfram
full_name: Kollatschny, Wolfram
last_name: Kollatschny
- first_name: Raffaella Anna
full_name: Marino, Raffaella Anna
last_name: Marino
- first_name: Michael
full_name: Maseda, Michael
last_name: Maseda
- first_name: Jorryt J
full_name: Matthee, Jorryt J
id: 7439a258-f3c0-11ec-9501-9df22fe06720
last_name: Matthee
orcid: 0000-0003-2871-127X
- first_name: Mieke
full_name: Paalvast, Mieke
last_name: Paalvast
- first_name: Johan
full_name: Richard, Johan
last_name: Richard
- first_name: Anne
full_name: Verhamme, Anne
last_name: Verhamme
citation:
ama: Nanayakkara T, Brinchmann J, Boogaard L, et al. Exploring He II λ1640 emission
line properties at z ∼2−4. Astronomy & Astrophysics. 2019;648. doi:10.1051/0004-6361/201834565
apa: Nanayakkara, T., Brinchmann, J., Boogaard, L., Bouwens, R., Cantalupo, S.,
Feltre, A., … Verhamme, A. (2019). Exploring He II λ1640 emission line properties
at z ∼2−4. Astronomy & Astrophysics. EDP Sciences. https://doi.org/10.1051/0004-6361/201834565
chicago: Nanayakkara, Themiya, Jarle Brinchmann, Leindert Boogaard, Rychard Bouwens,
Sebastiano Cantalupo, Anna Feltre, Wolfram Kollatschny, et al. “Exploring He II Λ1640
Emission Line Properties at z ∼2−4.” Astronomy & Astrophysics. EDP
Sciences, 2019. https://doi.org/10.1051/0004-6361/201834565.
ieee: T. Nanayakkara et al., “Exploring He II λ1640 emission line properties
at z ∼2−4,” Astronomy & Astrophysics, vol. 648. EDP Sciences, 2019.
ista: Nanayakkara T, Brinchmann J, Boogaard L, Bouwens R, Cantalupo S, Feltre A,
Kollatschny W, Marino RA, Maseda M, Matthee JJ, Paalvast M, Richard J, Verhamme
A. 2019. Exploring He II λ1640 emission line properties at z ∼2−4. Astronomy &
Astrophysics. 648, A89.
mla: Nanayakkara, Themiya, et al. “Exploring He II Λ1640 Emission Line Properties
at z ∼2−4.” Astronomy & Astrophysics, vol. 648, A89, EDP Sciences,
2019, doi:10.1051/0004-6361/201834565.
short: T. Nanayakkara, J. Brinchmann, L. Boogaard, R. Bouwens, S. Cantalupo, A.
Feltre, W. Kollatschny, R.A. Marino, M. Maseda, J.J. Matthee, M. Paalvast, J.
Richard, A. Verhamme, Astronomy & Astrophysics 648 (2019).
date_created: 2022-07-06T09:07:06Z
date_published: 2019-04-16T00:00:00Z
date_updated: 2022-07-19T09:36:08Z
day: '16'
doi: 10.1051/0004-6361/201834565
extern: '1'
external_id:
arxiv:
- '1902.05960'
intvolume: ' 648'
keyword:
- Space and Planetary Science
- Astronomy and Astrophysics
- 'galaxies: ISM / galaxies: star formation / galaxies: evolution / galaxies: high-redshift'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1902.05960
month: '04'
oa: 1
oa_version: Published Version
publication: Astronomy & Astrophysics
publication_identifier:
eissn:
- 1432-0746
issn:
- 0004-6361
publication_status: published
publisher: EDP Sciences
quality_controlled: '1'
related_material:
link:
- relation: erratum
url: https://doi.org/10.1051/0004-6361/201834565e
scopus_import: '1'
status: public
title: Exploring He II λ1640 emission line properties at z ∼2−4
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 648
year: '2019'
...
---
_id: '11572'
abstract:
- lang: eng
text: We present spectroscopic follow-up of candidate luminous Ly α emitters (LAEs)
at z = 5.7–6.6 in the SA22 field with VLT/X-SHOOTER. We confirm two new luminous
LAEs at z = 5.676 (SR6) and z = 6.532 (VR7), and also present HST follow-up of
both sources. These sources have luminosities LLy α ≈ 3 × 1043 erg s−1, very high
rest-frame equivalent widths of EW0 ≳ 200 Å and narrow Ly α lines (200–340 km s−1).
VR7 is the most UV-luminous LAE at z > 6.5, with M1500 = −22.5, even brighter
in the UV than CR7. Besides Ly α, we do not detect any other rest-frame UV lines
in the spectra of SR6 and VR7, and argue that rest-frame UV lines are easier to
observe in bright galaxies with low Ly α equivalent widths. We confirm that Ly α
line widths increase with Ly α luminosity at z = 5.7, while there are indications
that Ly α lines of faint LAEs become broader at z = 6.6, potentially due to reionization.
We find a large spread of up to 3 dex in UV luminosity for >L⋆ LAEs, but find
that the Ly α luminosity of the brightest LAEs is strongly related to UV luminosity
at z = 6.6. Under basic assumptions, we find that several LAEs at z ≈ 6–7 have
Ly α escape fractions ≳ 100 per cent, indicating bursty star formation histories,
alternative Ly α production mechanisms, or dust attenuating Ly α emission differently
than UV emission. Finally, we present a method to compute ξion, the production
efficiency of ionizing photons, and find that LAEs at z ≈ 6–7 have high values
of log10(ξion/Hz erg−1) ≈ 25.51 ± 0.09 that may alleviate the need for high Lyman-Continuum
escape fractions required for reionization.
acknowledgement: 'We thank the referee for a constructive report that has improved
the quality and clarity of this work. The authors thank Grecco Oyarzún for discussions.
JM acknowledges the support of a Huygens PhD fellowship from Leiden University.
DS acknowledges financial support from the Netherlands Organisation for Scientific
research (NWO) through a Veni fellowship and from Lancaster University through an
Early Career Internal Grant A100679. BD acknowledges financial support from NASA
through the Astrophysics Data Analysis Program (ADAP), grant number NNX12AE20G.
We thank Kasper Schmidt for providing measurements. Based on observations with the
W.M. Keck Observatory through programme C267D. The W.M. Keck Observatory is operated
as a scientific partnership amongst the California Institute of Technology, the
University of California and the National Aeronautics and Space Administration.
Based on observations made with ESO Telescopes at the La Silla Paranal Observatory
under programme IDs 097.A-0943, 294.A 5018 and 098.A-0819 and on data products produced
by TERAPIX and the Cambridge Astronomy Survey Unit on behalf of the UltraVISTA consortium.
The authors acknowledge the award of observing time (W16AN004) and of service time
(SW2014b20) on the William Herschel Telescope (WHT). WHT and its service programme
are operated on the island of La Palma by the Isaac Newton Group in the Spanish
Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias.
Based on observations made with the NASA/ESA HST, obtained (from the Data Archive)
at the Space Telescope Science Institute, which is operated by the Association of
Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These
observations are associated with programme #14699. We are grateful for the excellent
data sets from the COSMOS, UltraVISTA, SXDS, UDS and CFHTLS survey teams; without
these legacy surveys, this research would have been impossible. We have benefited
from the public available programming language PYTHON, including the NUMPY, MATPLOTLIB,
PYFITS, SCIPY and ASTROPY packages, the astronomical imaging tools SEXTRACTOR, SWARP
and SCAMP and the TOPCAT analysis tool (Taylor 2013).'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Jorryt J
full_name: Matthee, Jorryt J
id: 7439a258-f3c0-11ec-9501-9df22fe06720
last_name: Matthee
orcid: 0000-0003-2871-127X
- first_name: David
full_name: Sobral, David
last_name: Sobral
- first_name: Behnam
full_name: Darvish, Behnam
last_name: Darvish
- first_name: Sérgio
full_name: Santos, Sérgio
last_name: Santos
- first_name: Bahram
full_name: Mobasher, Bahram
last_name: Mobasher
- first_name: Ana
full_name: Paulino-Afonso, Ana
last_name: Paulino-Afonso
- first_name: Huub
full_name: Röttgering, Huub
last_name: Röttgering
- first_name: Lara
full_name: Alegre, Lara
last_name: Alegre
citation:
ama: Matthee JJ, Sobral D, Darvish B, et al. Spectroscopic properties of luminous
Ly α emitters at z ≈ 6–7 and comparison to the Lyman-break population. Monthly
Notices of the Royal Astronomical Society. 2017;472(1):772-787. doi:10.1093/mnras/stx2061
apa: Matthee, J. J., Sobral, D., Darvish, B., Santos, S., Mobasher, B., Paulino-Afonso,
A., … Alegre, L. (2017). Spectroscopic properties of luminous Ly α emitters at
z ≈ 6–7 and comparison to the Lyman-break population. Monthly Notices of the
Royal Astronomical Society. Oxford University Press. https://doi.org/10.1093/mnras/stx2061
chicago: Matthee, Jorryt J, David Sobral, Behnam Darvish, Sérgio Santos, Bahram
Mobasher, Ana Paulino-Afonso, Huub Röttgering, and Lara Alegre. “Spectroscopic
Properties of Luminous Ly α Emitters at z ≈ 6–7 and Comparison to the Lyman-Break
Population.” Monthly Notices of the Royal Astronomical Society. Oxford
University Press, 2017. https://doi.org/10.1093/mnras/stx2061.
ieee: J. J. Matthee et al., “Spectroscopic properties of luminous Ly α emitters
at z ≈ 6–7 and comparison to the Lyman-break population,” Monthly Notices of
the Royal Astronomical Society, vol. 472, no. 1. Oxford University Press,
pp. 772–787, 2017.
ista: Matthee JJ, Sobral D, Darvish B, Santos S, Mobasher B, Paulino-Afonso A, Röttgering
H, Alegre L. 2017. Spectroscopic properties of luminous Ly α emitters at z ≈ 6–7
and comparison to the Lyman-break population. Monthly Notices of the Royal Astronomical
Society. 472(1), 772–787.
mla: Matthee, Jorryt J., et al. “Spectroscopic Properties of Luminous Ly α Emitters
at z ≈ 6–7 and Comparison to the Lyman-Break Population.” Monthly Notices of
the Royal Astronomical Society, vol. 472, no. 1, Oxford University Press,
2017, pp. 772–87, doi:10.1093/mnras/stx2061.
short: J.J. Matthee, D. Sobral, B. Darvish, S. Santos, B. Mobasher, A. Paulino-Afonso,
H. Röttgering, L. Alegre, Monthly Notices of the Royal Astronomical Society 472
(2017) 772–787.
date_created: 2022-07-13T09:47:39Z
date_published: 2017-11-01T00:00:00Z
date_updated: 2022-08-19T08:05:37Z
day: '01'
doi: 10.1093/mnras/stx2061
extern: '1'
external_id:
arxiv:
- '1706.06591'
intvolume: ' 472'
issue: '1'
keyword:
- Space and Planetary Science
- Astronomy and Astrophysics
- 'galaxies: evolution – galaxies: high-redshift'
- dark ages
- reionization
- first stars
- 'cosmology: observations'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1706.06591
month: '11'
oa: 1
oa_version: Preprint
page: 772-787
publication: Monthly Notices of the Royal Astronomical Society
publication_identifier:
eissn:
- 1365-2966
issn:
- 0035-8711
publication_status: published
publisher: Oxford University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Spectroscopic properties of luminous Ly α emitters at z ≈ 6–7 and comparison
to the Lyman-break population
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 472
year: '2017'
...