The COS Absorption Survey of Baryon Harbors: The Galaxy Database and
  Cross-Correlation Analysis of OVI Systems
  We describe the survey for galaxies in the fields surrounding 9 sightlines to
far-UV bright, z~1 quasars that define the COS Absorption Survey of Baryon
Harbors (CASBaH) program. The photometry and spectroscopy that comprise the
dataset come from a mixture of public surveys (SDSS, DECaLS) and our dedicated
efforts on private facilities (Keck, MMT, LBT). We report the redshifts and
stellar masses for 5902 galaxies within ~10 comoving-Mpc (cMpc) of the
sightlines with a median of z=0.28 and M_* ~ 10^(10.1) Msun. This dataset,
publicly available as the CASBaH specDB, forms the basis of several recent and
ongoing CASBaH analyses. Here, we perform a clustering analysis of the galaxy
sample with itself (auto-correlation) and against the set of OVI absorption
systems (cross-correlation) discovered in the CASBaH quasar spectra with column
densities N(O^+5) >= 10^(13.5)/cm^2. For each, we describe the measured
clustering signal with a power-law correlation function xi(r) =
(r/r_0)^(-gamma) and find that (r_0,gamma) = (5.48 +/- 0.07 h_100^-1 Mpc, 1.33
+/- 0.04) for the auto-correlation and (6.00 +/- 1 h^-1 Mpc, 1.25 +/- 0.18) for
galaxy-OVI cross-correlation. We further estimate a bias factor of b_gg = 1.3
+/- 0.1 from the galaxy-galaxy auto-correlation indicating the galaxies are
hosted by halos with mass M_halo ~ 10^(12.1 +/- 0.05) Msun. Finally, we
estimate an OVI-galaxy bias factor b_OVI = 1.0 +/- 0.1 from the
cross-correlation which is consistent with OVI absorbers being hosted by dark
matter halos with typical mass M_halo ~ 10^(11) Msun. Future works with
upcoming datasets (e.g., CGM^2) will improve upon these results and will assess
whether any of the detected OVI arises in the intergalactic medium.
