TY - JOUR
T1 - Probing the cool interstellar and circumgalactic gas of three massive lensing galaxies at z = 0.4-0.7
AU - Zahedy, Fakhri S.
AU - Chen, Hsiao Wen
AU - Rauch, Michael
AU - Wilson, Michelle L.
AU - Zabludoff, Ann
N1 - Funding Information:
This work is based on data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, the ESO telescopes at the La Silla ParanalObservatory, and the NASA/ESA HST operated by the Space Telescope Science Institute and the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. Additional data were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of theW. M. Keck Foundation. We thank an anonymous referee for thoughtful comments that helped improve the presentation of the paper, Frederic Courbin for kindly providing the spectra of the lensing galaxies of HE 0047-1756 and HE 0435-1223 (data obtained using the ESO-VLT Unit Telescope 2 Kueyen under programmes 074.A-0563 and 075.A-0377), and Sebastián Lopeź for providing the echelle spectra of HE 1104-1805 (data obtained using the ESOVLT Unit Telescope 2 Kueyen under programmes 067.A-0278 and 070.A-0439). FSZ and HWC thank Sean Johnson for important discussions and comments that helped improve the presentation of the paper. We also thank Rebecca Pierce for helpful comments on an earlier draft of the paper. MR thanks Andy McWilliam for useful discussions and the National Science Foundation for support through grant AST-1108815. MLW and AIZ acknowledge funding from NSF grant AST-1211874 and NASA grant ADP-10AE88G. MLW also thanks the Technology and Research Initiative Fund (TRIF) Imaging Fellowship programme for its support. In addition, HWC acknowledges the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1066293, and the organizers of the workshop on the 'physics of accretion and feedback in the CGM' for a productive visit in 2015 June, during which components of the work presented were accomplished.
Publisher Copyright:
© 2016 The Authors.
PY - 2016/3/8
Y1 - 2016/3/8
N2 - We present multisightline absorption spectroscopy of cool gas around three lensing galaxies at z = 0.4-0.7. These lenses have half-light radii re = 2.6-8 kpc and stellar masses of log M*/M⊙ = 10.9-11.4, and therefore resemble nearby passive elliptical galaxies. The lensed QSO sightlines presented here occur at projected distances of d = 3-15 kpc (or d ≈ 1-2 re) from the lensing galaxies, providing for the first time an opportunity to probe both interstellar gas at r ~ re and circumgalactic gas at larger radii r ≫ re of these distant quiescent galaxies. We observe distinct gas absorption properties among different lenses and among sightlines of individual lenses. Specifically, while the quadruple lens for HE 0435-1223 shows no absorption features to very sensitive limits along all four sightlines, strong Mg ii, Fe ii, Mg i, and Ca ii absorption transitions are detected along both sightlines near the double lens for HE 0047-1756, and in one of the two sightlines near the double lens for HE 1104-1805. The absorbers are resolved into 8-15 individual components with a line-of-sight velocity spread of Δ v ≈ 300-600 km s-1. The large ionic column densities, log N ≤ 14, observed in two components suggest that these may be Lyman limit or damped Ly α absorbers with a significant neutral hydrogen fraction. The majority of the absorbing components exhibit a uniform supersolar Fe/Mg ratio with a scatter of <0.1 dex across the full Δ v range. Given a predominantly old stellar population in these lensing galaxies, we argue that the observed large velocity width and Fe-rich abundance pattern can be explained by SNe Ia enriched gas at radius r ~ re. We show that additional spatial constraints in line-of-sight velocity and relative abundance ratios afforded by a multisightline approach provide a powerful tool to resolve the origin of chemically enriched cool gas in massive haloes.
AB - We present multisightline absorption spectroscopy of cool gas around three lensing galaxies at z = 0.4-0.7. These lenses have half-light radii re = 2.6-8 kpc and stellar masses of log M*/M⊙ = 10.9-11.4, and therefore resemble nearby passive elliptical galaxies. The lensed QSO sightlines presented here occur at projected distances of d = 3-15 kpc (or d ≈ 1-2 re) from the lensing galaxies, providing for the first time an opportunity to probe both interstellar gas at r ~ re and circumgalactic gas at larger radii r ≫ re of these distant quiescent galaxies. We observe distinct gas absorption properties among different lenses and among sightlines of individual lenses. Specifically, while the quadruple lens for HE 0435-1223 shows no absorption features to very sensitive limits along all four sightlines, strong Mg ii, Fe ii, Mg i, and Ca ii absorption transitions are detected along both sightlines near the double lens for HE 0047-1756, and in one of the two sightlines near the double lens for HE 1104-1805. The absorbers are resolved into 8-15 individual components with a line-of-sight velocity spread of Δ v ≈ 300-600 km s-1. The large ionic column densities, log N ≤ 14, observed in two components suggest that these may be Lyman limit or damped Ly α absorbers with a significant neutral hydrogen fraction. The majority of the absorbing components exhibit a uniform supersolar Fe/Mg ratio with a scatter of <0.1 dex across the full Δ v range. Given a predominantly old stellar population in these lensing galaxies, we argue that the observed large velocity width and Fe-rich abundance pattern can be explained by SNe Ia enriched gas at radius r ~ re. We show that additional spatial constraints in line-of-sight velocity and relative abundance ratios afforded by a multisightline approach provide a powerful tool to resolve the origin of chemically enriched cool gas in massive haloes.
KW - Galaxies: Elliptical and lenticular, cD
KW - Galaxies: Haloes
KW - Galaxies: Kinematics and dynamics
KW - Quasars: Absorption lines
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U2 - 10.1093/mnras/stw484
DO - 10.1093/mnras/stw484
M3 - Article
AN - SCOPUS:84964778161
SN - 0035-8711
VL - 458
SP - 2423
EP - 2442
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 3
ER -