The GOGREEN and GCLASS Surveys: First Data Release

TL;DR

This paper announces the first public data release from the GOGREEN and GCLASS galaxy surveys, providing extensive multiwavelength photometry and spectroscopy of galaxies in dense environments at redshifts 0.8 to 1.5, aimed at understanding environmental effects on galaxy evolution.

Contribution

It provides the first comprehensive data release including images, spectra, and catalogs from the GOGREEN and GCLASS surveys, enabling detailed studies of galaxy quenching and environmental influence.

Findings

Spectroscopic sample includes 2771 objects with 2257 reliable redshifts.

Nearly 800 galaxies confirmed as cluster members.

Data spans optical to near-infrared wavelengths with high depth.

Abstract

We present the first public data release of the GOGREEN and GCLASS surveys of galaxies in dense environments, spanning a redshift range $0.8<z<1.5$. The surveys consist of deep, multiwavelength photometry and extensive Gemini GMOS spectroscopy of galaxies in 26 overdense systems ranging in halo mass from small groups to the most massive clusters. The objective of both projects was primarily to understand how the evolution of galaxies is affected by their environment, and to determine the physical processes that lead to the quenching of star formation. There was an emphasis on obtaining unbiased spectroscopy over a wide stellar mass range ($M\gtrsim 2\times 10^{10}~\mathrm{M}_\odot$), throughout and beyond the cluster virialized regions. The final spectroscopic sample includes 2771 unique objects, of which 2257 have reliable spectroscopic redshifts. Of these, 1704 have redshifts in the range $0.8<z<1.5$, and nearly 800 are confirmed cluster members. Imaging spans the full optical and near-infrared wavelength range, at depths comparable to the UltraVISTA survey, and includes \textit{HST}/WFC3 F160W (GOGREEN) and F140W (GCLASS). This data release includes fully reduced images and spectra, with catalogues of advanced data products including redshifts, line strengths, star formation rates, stellar masses and rest-frame colours. Here we present an overview of the data, including an analysis of the spectroscopic completeness and redshift quality.