Characterizing the Circumgalactic Medium of Nearby Galaxies with HST/COS
  and HST/STIS Absorption-Line Spectroscopy: II. Methods and Models
  We present basic data and modeling for a survey of the cool, photo-ionized
Circum-Galactic Medium (CGM) of low-redshift galaxies using far-UV QSO
absorption line probes. This survey consists of "targeted" and "serendipitous"
CGM subsamples, originally described in Stocke et al. (2013, Paper 1). The
targeted subsample probes low-luminosity, late-type galaxies at $z<0.02$ with
small impact parameters ($\langle\rho\rangle = 71$ kpc), and the serendipitous
subsample probes higher luminosity galaxies at $z\lesssim0.2$ with larger
impact parameters ($\langle\rho\rangle = 222$ kpc). HST and FUSE UV
spectroscopy of the absorbers and basic data for the associated galaxies,
derived from ground-based imaging and spectroscopy, are presented. We find
broad agreement with the COS-Halos results, but our sample shows no evidence
for changing ionization parameter or hydrogen density with distance from the
CGM host galaxy, probably because the COS-Halos survey probes the CGM at
smaller impact parameters. We find at least two passive galaxies with H I and
metal-line absorption, confirming the intriguing COS-Halos result that galaxies
sometimes have cool gas halos despite no on-going star formation. Using a new
methodology for fitting H I absorption complexes, we confirm the CGM cool gas
mass of Paper 1, but this value is significantly smaller than found by the
COS-Halos survey. We trace much of this difference to the specific values of
the low-$z$ meta-galactic ionization rate assumed. After accounting for this
difference, a best-value for the CGM cool gas mass is found by combining the
results of both surveys to obtain $\log{(M/M_{\odot})}=10.5\pm0.3$, or ~30% of
the total baryon reservoir of an $L \geq L^*$, star-forming galaxy.
