Hα Emission and the Dependence of the Circumgalactic Cool Gas Fraction on Halo Mass
AffiliationUniv Arizona, Steward Observ
KeywordsGalactic and extragalactic astronomy
Intergalactic medium phases
Cool intergalactic medium
Emission line galaxies
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationHuanian Zhang et al 2020 ApJ 888 33
RightsCopyright © 2020. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractWe continue our empirical study of the emission line flux originating in the cool (T similar to 10(4) K) gas that populates the halos of galaxies and their environments. Specifically, we present results obtained for a sample of nearly half a million individual galaxies, groups, and clusters of galaxies, intersected by more than two million SDSS lines of sight at projected separations of up to a quarter of the virial radius. Adopting simple power-law relationships between the circumgalactic (CGM) cool gas fraction and either the halo or stellar mass, we present expressions for the CGM cool gas fraction as a function of either halo or stellar mass, . Where we can compare, our results are consistent with previous constraints from absorption line studies, our own previous emission line work, and simulations. The cool gas can be the dominant baryonic CGM component, comprising a fraction as high as >90% of halo gaseous baryons, in low-mass halos, M-h similar to 10(10.5) M, and a minor fraction, <5%, in groups and clusters, M-h > 10(14) M.
VersionFinal published version