Distribution of Cold ($\lesssim 300$K) Atomic Gas in Galaxies: Results from the GBT HI Absorption Survey Probing the Inner Halos ($\rho <20$kpc) of Low-z Galaxies

Abstract

We present the Green Bank Telescope absorption survey of cold atomic hydrogen ($\lesssim 300$K) in the inner halo of low-redshift galaxies. The survey aims to characterize the cold gas distribution and to address where condensation - the process where ionized gas accreted by galaxies condenses into cold gas within the disks of galaxies - occurs. Our sample consists of 16 galaxy-quasar pairs with impact parameters of $\le$ 20kpc. We detected an HI absorber associated with J0958+3222 (NGC 3067) and HI emission from six galaxies. We also found two \ion{Ca}{2} absorption system in the archival SDSS data associated with galaxies J0958+3222 and J1228+3706, although the sample was not selected based on the presence of metals in absorption. Our detection rate of HI absorbers with optical depths of $\ge 0.06$ is $\sim$7\%. We also find that cold HI phase ($\lesssim$300K) is 44($\pm$18)\% of the total atomic gas in the sightline probing J0958+3222. We find no correlation between the peak optical depth and impact parameter or stellar and HI radii normalized impact parameters, $\rho /{\mathrm{R}}_{90}$ and $\rho /{\mathrm{R}}_{\mathrm{HI}}$. We conclude that the process of condensation of inflowing gas into cold ($\lesssim$ 300K) HI occurs at the $\rho <<20$kpc. However, the warmer phase of neutral gas (T $\sim$ 1000K) can exists out to much larger distances as seen in emission maps. Therefore, the process of condensation of warm to cold HI is likely occurring in stages from ionized to warm HI in the inner halo and then to cold HI very close to the galaxy disk.

arXiv commentAccepted for publication in ApJ. Contains 12 pages, 7 figures, and 2 tables

References in corpus (41)

• The Seventh Data Release of the Sloan Digital Sky Survey
• How Do Galaxies Get Their Gas?
• NYU-VAGC: a galaxy catalog based on new public surveys
• Virial shocks in galactic haloes?
• The COS-Halos Survey: Physical Conditions and Baryonic Mass in the Low-Redshift Circumgalactic Medium
• The Importance of Satellite Quenching for the Build-Up of the Red Sequence of Present Day Galaxies
• The COS-Halos Survey: Rationale, Design, and A Census of Circumgalactic Neutral Hydrogen
• Efficient Photometric Selection of Quasars from the Sloan Digital Sky Survey: II. ~1,000,000 Quasars from Data Release Six
• The cold gaseous halo of NGC 891
• Probing the IGM/Galaxy Connection V: On the Origin of Lya and OVI Absorption at z<0.2
• The Westerbork HI Survey of Spiral and Irregular Galaxies I. HI Imaging of Late-type Dwarf Galaxies
• Characterizing the Circumgalactic Medium of Nearby Galaxies with HST/COS and HST/STIS Absorption-Line Spectroscopy
• Global properties of the HI distribution in the outer Milky Way
• The Westerbork Hydrogen Accretion in Local Galaxies (HALOGAS) Survey I. Survey Description and Pilot Observations
• The Relationship Between Galaxies and Low Redshift Weak Lyman alpha Absorbers in the Directions of H1821+643 and PG1116+215
• The Gaseous Extent of Galaxies and the Origin of \lya Absorption Systems. III. Hubble Space Telescope Imaging of \lya-Absorbing Galaxies at z < 1
• Mining Circumgalactic Baryons in the Low-Redshift Universe
• The Gaseous Extent of Galaxies and the Origin of Lya Absorption Systems. V. Optical and Near-Infrared Photometry of Lya-absorbing Galaxies at z < 1
• Connection Between the Circumgalactic Medium and the Interstellar Medium of Galaxies: Results from the COS-GASS Survey
• High-velocity clouds as streams of ionized and neutral gas in the halo of the Milky Way
• Absorption Systems in the Spectra of 66 z > 4 Quasars
• Discovery of a Population of HI Clouds in the Galactic Halo
• The Impact of Starbursts on the Circumgalactic Medium
• A search for HI absorption in nearby radio galaxies using HIPASS
• Lyman-alpha absorption around nearby galaxies
• HI 21cm absorption in low z damped lyman-alpha systems
• Search for cold gas in strong MgII absorbers at 0.5<z<1.5: nature and evolution of 21-cm absorbers
• Parsec-scale structures and diffuse bands in a translucent interstellar medium at z 0.079
• Using 21cm Absorption in Small Impact Parameter Galaxy-QSO Pairs to Probe Low-Redshift Damped and Sub-Damped Lyman-alpha System
• Probing the gas content of radio galaxies through HI absorption stacking
• GMRT mini-survey to search for 21-cm absorption in Quasar-Galaxy Pairs at z~0.1
• 21-cm absorption from galaxies at z ~ 0.3
• Absorption Line Study of Halo Gas in NGC 3067 Toward the Background Quasar 3C 232
• HI emission and absorption in nearby, gas-rich galaxies II. -- sample completion and detection of intervening absorption in NGC 5156
• New HI 21-cm absorbers at low and intermediate redshifts
• A GBT Survey for HI 21 cm Absorption in the Disks and Halos of Low-Redshift Galaxies
• A correlation between the HI 21-cm absorption strength and impact parameter in external galaxies
• Mapping kiloparsec-scale structures in the extended HI disc of the galaxy UGC 00439 by HI 21-cm absorption
• HI emission and absorption in nearby, gas-rich galaxies
• Small-scale Properties of Atomic Gas in Extended Disks of Galaxies
• A new 21-cm absorber identified with an $L\sim L^{\star }$ galaxy

Cited by in corpus (13)

• FLASH Early Science -- Discovery of an intervening HI 21-cm absorber from an ASKAP survey of the GAMA 23 field
• The First Large Absorption Survey in HI (FLASH): I. Science Goals and Survey Design
• HI 21-cm absorption survey of quasar-galaxy pairs: Distribution of cold gas around z<0.4 galaxies
• Revealing HI gas in emission and absorption on pc to kpc scales in a galaxy at z ~ 0.017
• A statistical measurement of the HI spin temperature in DLAs at cosmological distances
• HI 21-cm absorption from $z\sim 0.35$ strong MgII absorbers
• Probing galaxy evolution through HI 21-cm emission and absorption: current status and prospects with the Square Kilometre Array
• Observations of cold extragalactic gas clouds at $z=0.45$ towards PKS 1610-771
• Cold neutral hydrogen gas in galaxies
• DIISC-I: The Discovery of Kinematically Anomalous HI Clouds in M 100
• Discovery of a Low-Redshift Damped Ly$\alpha$ System in a Foreground Extended Disk Using a Starburst Galaxy Background Illuminator
• Disc galaxy resolved in HI absorption against the radio lobe of 3C 433: Case study for future surveys
• High spin temperatures at large impact parameters: Ionisation in the outskirts of galaxies