Probing the IGM/Galaxy Connection IV: The LCO/WFCCD Galaxy Survey of 20 Fields Surrounding UV Bright Quasars

TL;DR

This survey of 20 quasar fields provides a comprehensive catalog of galaxies, including dwarf galaxies, around UV-bright quasars to study their association with the low-redshift intergalactic medium, with detailed imaging and spectroscopic data.

Contribution

First large-scale, magnitude-limited galaxy survey around UV-bright quasars designed to explore galaxy-IGM connections at low redshift, with extensive photometric and spectroscopic data.

Findings

Catalog of 84718 sources with photometry

Redshifts for 2800 galaxies, including 1198 likely associated with IGM

Data available online for further analysis

Abstract

We publish the survey for galaxies in 20 fields containing ultraviolet bright quasars (with z_em 0.1 to 0.5) that can be used to study the association between galaxies and absorption systems from the low-z intergalactic medium (IGM). The survey is magnitude limited (R~19.5 mag) and highly complete out to 10' from the quasar in each field. It was designed to detect dwarf galaxies (L ~ 0.1 L*) at an impact parameter rho 1Mpc (z=0.1) from a quasar. The complete sample (all 20 fields) includes R-band photometry for 84718 sources and confirmed redshifts for 2800 sources. This includes 1198 galaxies with 0.005 < z < (z_em - 0.01) at a median redshift of 0.18, which may associated with IGM absorption lines. All of the imaging was acquired with cameras on the Swope 40" telescope and the spectra were obtained via slitmask observations using the WFCCD spectrograph on the Dupont 100" telescope at Las Campanas Observatory (LCO). This paper describes the data reduction, imaging analysis, photometry, and spectral analysis of the survey. We tabulate the principal measurements for all sources in each field and provide the spectroscopic dataset online.