Bibliographic Details
| Title: |
The Cosmic Ultraviolet Baryon Survey (CUBS) II: Discovery of an H$_{2}$-Bearing DLA in the Vicinity of an Early-Type Galaxy at z = 0.576 |
| Authors: |
Boettcher, Erin, Chen, Hsiao-Wen, Zahedy, Fakhri S., Cooper, Thomas J., Johnson, Sean D., Rudie, Gwen C., Chen, Mandy C., Petitjean, Patrick, Cantalupo, Sebastiano, Cooksey, Kathy L., Faucher-Giguère, Claude-André, Greene, Jenny E., Lopez, Sebastian, Mulchaey, John S., Penton, Steven V., Putman, Mary E., Rafelski, Marc, Rauch, Michael, Schaye, Joop, Simcoe, Robert A., Walth, Gregory L. |
| Publication Year: |
2020 |
| Collection: |
Astrophysics |
| Subject Terms: |
Astrophysics - Astrophysics of Galaxies |
| More Details: |
We report the serendipitous detection of an H$_{2}$-bearing damped Lyman-$\alpha$ absorber at z = 0.576 in the spectrum of the QSO J0111-0316 in the Cosmic Ultraviolet Baryon Survey. Spectroscopic observations from HST-COS in the far-ultraviolet reveal a damped absorber with log[N(HI)/cm^-2] = 20.1 +/- 0.2 and log[N(H$_{2}$)/cm^-2] = 18.97 (-0.06, +0.05). The diffuse molecular gas is found in two velocity components separated by dv = 60 km/s, with >99.9% of the total H$_{2}$ column density concentrated in one component. At a metallicity of $\approx$ 50% of solar, there is evidence for Fe enhancement and dust depletion, with a dust-to-gas ratio $\kappa_{\text{O}} \approx$ 0.4. A galaxy redshift survey conducted with IMACS and LDSS-3C on Magellan reveals an overdensity of nine galaxies at projected distance d <= 600 proper kpc (pkpc) and line-of-sight velocity offset dv$_{g}$ <= 300 km/s from the absorber. The closest is a massive, early-type galaxy at d = 41 pkpc which contains $\approx$ 70% of the total stellar mass identified at d <= 310 pkpc of the H$_{2}$ absorber. The close proximity of the H$_{2}$-bearing gas to the quiescent galaxy and the Fe-enhanced chemical abundance pattern of the absorber suggest a physical connection, in contrast to a picture in which DLAs are primarily associated with gas-rich dwarfs. This case study illustrates that deep galaxy redshift surveys are needed to gain insight into the diverse environments that host dense and potentially star-forming gas.
Comment: 19 pages, 6 figures. Accepted for publication in ApJ |
| Document Type: |
Working Paper |
| DOI: |
10.3847/1538-4357/abf0a0 |
| Access URL: |
http://arxiv.org/abs/2010.11958 |
| Accession Number: |
edsarx.2010.11958 |
| Database: |
arXiv |
