We describe the survey for galaxies in the fields surrounding 9 sightlines to far-UV bright , z \sim 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 \approx 10 comoving-Mpc ( cMpc ) of the sightlines with a median of \bar { z } = 0.28 and \bar { M } _ { * } \approx 10 ^ { 10.1 } M _ { \odot } .
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 \ion O6 absorption systems ( cross-correlation ) discovered in the CASBaH quasar spectra with column densities { N ( { O ^ { +5 } } ) } \geq 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 \pm 0.07 h _ { 100 } ^ { -1 } { Mpc } , 1.33 \pm 0.04 ) for the auto-correlation and ( 6.00 ^ { +1.09 } _ { -0.77 } h _ { 100 } ^ { -1 } { Mpc } , 1.25 \pm 0.18 ) for galaxy- \ion O6 cross-correlation .
We further estimate a bias factor of b _ { gg } = 1.3 \pm 0.1 from the galaxy-galaxy auto-correlation indicating the galaxies are hosted by halos with mass M _ { halo } \approx 10 ^ { 12.1 \pm 0.05 } M _ { \odot } .
Finally , we estimate an \ion O6-galaxy bias factor b _ { OVI } = 1.0 \pm 0.1 from the cross-correlation which is consistent with \ion O6 absorbers being hosted by dark matter halos with typical mass M _ { halo } \approx 10 ^ { 11 } M _ { \odot } .
Future works with upcoming datasets ( e.g. , CGM ^ { 2 } ) will improve upon these results and will assess whether any of the detected \ion O6 arises in the intergalactic medium .