TY - JOUR
T1 - A young star-forming galaxy at z = 3.5 with an extended Ly\,$α$ halo seen with MUSE
AU - Patrício, Vera
AU - Richard, Johan
AU - Verhamme, Anne
AU - Wisotzki, Lutz
AU - Brinchmann, Jarle
AU - Turner, Monica L.
AU - Christensen, Lise Bech
AU - Weilbacher, Peter M.
AU - Blaizot, Jérémy
AU - Bacon, Roland
AU - Contini, Thierry
AU - Lagattuta, David
AU - Cantalupo, Sebastiano
AU - Clément, Benjamin
AU - Soucail, Geneviève
N1 - 19 pages, 15 figures, accepted in MNRAS
PY - 2016/1/9
Y1 - 2016/1/9
N2 - Spatially resolved studies of high-redshift galaxies, an essential insight into galaxy formation processes, have been mostly limited to stacking or unusually bright objects. We present here the study of a typical (L *, M = 6 × 109M⊙) young lensed galaxy at z = 3.5, observed with Multi Unit Spectroscopic Explorer (MUSE), for which we obtain 2D resolved spatial information of Lyα and, for the first time, of C III] emission. The exceptional signal-to-noise ratio of the data reveals UV emission and absorption lines rarely seen at these redshifts, allowing us to derive important physical properties (Te ~ 15600 K, ne ~ 300 cm-3, covering fraction fc ~ 0.4) using multiple diagnostics. Inferred stellar and gas-phase metallicities point towards a low-metallicity object (Zstellar = ~ 0.07 Z⊙ and ZISM < 0.16 Z⊙). The Lyα emission extends over ~10 kpc across the galaxy and presents a very uniform spectral profile, showing only a small velocity shift which is unrelated to the intrinsic kinematics of the nebular emission. The Lya extension is approximately four times larger than the continuum emission, and makes this object comparable to low-mass LAEs at low redshift, and more compact than the Lyman-break galaxies and Lyα emitters usually studied at high redshift. We model the Lyα line and surface brightness profile using a radiative transfer code in an expanding gas shell, finding that this model provides a good description of both observables.
AB - Spatially resolved studies of high-redshift galaxies, an essential insight into galaxy formation processes, have been mostly limited to stacking or unusually bright objects. We present here the study of a typical (L *, M = 6 × 109M⊙) young lensed galaxy at z = 3.5, observed with Multi Unit Spectroscopic Explorer (MUSE), for which we obtain 2D resolved spatial information of Lyα and, for the first time, of C III] emission. The exceptional signal-to-noise ratio of the data reveals UV emission and absorption lines rarely seen at these redshifts, allowing us to derive important physical properties (Te ~ 15600 K, ne ~ 300 cm-3, covering fraction fc ~ 0.4) using multiple diagnostics. Inferred stellar and gas-phase metallicities point towards a low-metallicity object (Zstellar = ~ 0.07 Z⊙ and ZISM < 0.16 Z⊙). The Lyα emission extends over ~10 kpc across the galaxy and presents a very uniform spectral profile, showing only a small velocity shift which is unrelated to the intrinsic kinematics of the nebular emission. The Lya extension is approximately four times larger than the continuum emission, and makes this object comparable to low-mass LAEs at low redshift, and more compact than the Lyman-break galaxies and Lyα emitters usually studied at high redshift. We model the Lyα line and surface brightness profile using a radiative transfer code in an expanding gas shell, finding that this model provides a good description of both observables.
KW - astro-ph.GA
U2 - 10.1093/mnras/stv2859
DO - 10.1093/mnras/stv2859
M3 - Journal article
SN - 0035-8711
VL - 456
SP - 4191
EP - 4208
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -