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 $rm~M_*sim~10^{9.5-11.5}~M_{odot} $, and over a range of impact parameters extending to just beyond the halo virial radius ($rm~R_{vir}$). We find the radial scale length of the distributions of the equivalent widths of the Lyman~$alpha$ and Si III absorbers to be 0.9 and 0.4 $rm~R_{vir}$, respectively. The radial distribution of equivalent widths is relatively uniform for the blue galaxies, but highly patchy (low covering fraction) for the red galaxies. We also find that the Lyman~$alpha$ and 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 Lyman~$alpha$ lines. The ratio of the velocity offset to the velocity dispersion for the Lyman~$alpha$ absorbers has a mean value of $sim$ 4, suggesting that a given the 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 Lyman~$alpha$ velocity 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 specific star-formation rate across the galaxy mass-range we probe.
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