THE PROPERTIES of the CIRCUMGALACTIC MEDIUM in RED and BLUE GALAXIES: RESULTS from the COS-GASS+COS-HALOS SURVEYS

Sanchayeeta Borthakur, Timothy Heckman, Jason Tumlinson, Rongmon Bordoloi, Guinevere Kauffmann, Barbara Catinella, David Schiminovich, Romeel S Dave, Sean M. Moran, Amelie Saintonge

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

We use the combined data from the COS-GASS and COS-Halos surveys to characterize the Circum-Galactic Medium (CGM) surrounding typical low-redshift galaxies in the mass range M∗ ∼ 109.5-11.5 Ṁ, and over a range of impact parameters extending to just beyond the halo virial radius (Rvir). We find the radial scale length of the distributions of the equivalent widths of the Lyα and Si III absorbers to be ∼1 and ∼ 0.4 Rvir, respectively. The radial distribution of equivalent widths is relatively uniform for the blue galaxies, but highly patchy (i.e., it has a low covering fraction) for the red galaxies. We also find that the Lyαand Si III equivalent widths show significant positive correlations with the specific star formation rate (sSFR) of the galaxy. We find a surprising lack of correlations between the halo mass (virial velocity) and either the velocity dispersions or velocity offsets of the Lyαlines. The ratio of the velocity offset to the velocity dispersion for the Lyαabsorbers has a mean value of ∼4, suggesting that a given line of sight is intersecting a dynamically coherent structure in the CGM, rather than a sea of orbiting clouds. The kinematic properties of the CGM are similar in the blue and red galaxies, although we find that a significantly larger fraction of the blue galaxies have large Lyαvelocity offsets (>200 km s-1). We show that-if the CGM clouds represent future fuel for star formation-our new results could imply a large drop in the sSFR across the galaxy mass-range we probe.

Original languageEnglish (US)
Article number259
JournalAstrophysical Journal
Volume833
Issue number2
DOIs
StatePublished - Dec 20 2016
Externally publishedYes

Fingerprint

galaxies
halos
star formation rate
kinematics
probe
radial distribution
line of sight
star formation
absorbers
coverings
radii
probes
distribution
rate

Keywords

  • galaxies: halos
  • galaxies: star formation
  • quasars: absorption lines

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Borthakur, S., Heckman, T., Tumlinson, J., Bordoloi, R., Kauffmann, G., Catinella, B., ... Saintonge, A. (2016). THE PROPERTIES of the CIRCUMGALACTIC MEDIUM in RED and BLUE GALAXIES: RESULTS from the COS-GASS+COS-HALOS SURVEYS. Astrophysical Journal, 833(2), [259]. https://doi.org/10.3847/1538-4357/833/2/259

THE PROPERTIES of the CIRCUMGALACTIC MEDIUM in RED and BLUE GALAXIES : RESULTS from the COS-GASS+COS-HALOS SURVEYS. / Borthakur, Sanchayeeta; Heckman, Timothy; Tumlinson, Jason; Bordoloi, Rongmon; Kauffmann, Guinevere; Catinella, Barbara; Schiminovich, David; Dave, Romeel S; Moran, Sean M.; Saintonge, Amelie.

In: Astrophysical Journal, Vol. 833, No. 2, 259, 20.12.2016.

Research output: Contribution to journalArticle

Borthakur, S, Heckman, T, Tumlinson, J, Bordoloi, R, Kauffmann, G, Catinella, B, Schiminovich, D, Dave, RS, Moran, SM & Saintonge, A 2016, 'THE PROPERTIES of the CIRCUMGALACTIC MEDIUM in RED and BLUE GALAXIES: RESULTS from the COS-GASS+COS-HALOS SURVEYS', Astrophysical Journal, vol. 833, no. 2, 259. https://doi.org/10.3847/1538-4357/833/2/259
Borthakur, Sanchayeeta ; Heckman, Timothy ; Tumlinson, Jason ; Bordoloi, Rongmon ; Kauffmann, Guinevere ; Catinella, Barbara ; Schiminovich, David ; Dave, Romeel S ; Moran, Sean M. ; Saintonge, Amelie. / THE PROPERTIES of the CIRCUMGALACTIC MEDIUM in RED and BLUE GALAXIES : RESULTS from the COS-GASS+COS-HALOS SURVEYS. In: Astrophysical Journal. 2016 ; Vol. 833, No. 2.
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