Research Repository

See what's under the surface

# Determining the halo mass scale where galaxies lose their gas

## Authors

Gregory Rudnick

Pascale Jablonka

John Moustakas

Alfonso Aragón-Salamanca

Dennis Zaritsky

Yara L. Jaffe

Gabriella De Lucia

Vandana Desai

Claire Halliday

Dennis Just

Bo Milvang-Jensen

Bianca Poggianti

### Abstract

A major question in galaxy formation is how the gas supply that fuels activity in galaxies is modulated by their environment. We use spectroscopy of a set of well characterized clusters and groups at $0.45$\AA\ is $f_{[OII]}=0.08^{+0.03}_{-0.02}$ and $f_{[OII]}=0.06^{+0.07}_{-0.04}$ respectively. For field galaxies we find $f_{[OII]}=0.27^{+0.07}_{-0.06}$, representing a 2.8$\sigma$ difference between the [OII] fractions for old galaxies between the different environments. We conclude that a population of old galaxies in all environments has ionized gas that likely stems from stellar mass loss. In the field galaxies also experience gas accretion from the cosmic web and in groups and clusters these galaxies have had their gas accretion shut off by their environment. Additionally, galaxies with emission preferentially avoid the virialized region of the cluster in position-velocity space. We discuss the implications of our results, among which is that gas accretion shutoff is likely effective at group halo masses (log~${\cal M}/$\msol$>12.8$) and that there are likely multiple gas removal processes happening in dense environments.

Journal Article Type Article Nov 30, 2017 Astrophysical Journal 0004-637X 1538-4357 American Astronomical Society Peer Reviewed 850 2 181 Rudnick, G., Jablonka, P., Moustakas, J., Aragón-Salamanca, A., Zaritsky, D., Jaffe, Y. L., …Poggianti, B. (2017). Determining the halo mass scale where galaxies lose their gas. Astrophysical Journal, 850(2), doi:10.3847/1538-4357/aa866c https://doi.org/10.3847/1538-4357/aa866c Astrophysics - Astrophysics of Galaxies http://iopscience.iop.org/article/10.3847/1538-4357/aa866c/meta Copyright information regarding this work can be found at the following address: http://eprints.nottingh.../end_user_agreement.pdf

#### Files

Rudnick_2017_ApJ_850_181.pdf (1.6 Mb)
PDF