We present the first public data release of the GOGREEN (Gemini Observations of Galaxies in Rich Early Environments) and GCLASS (Gemini CLuster Astrophysics Spectroscopic Survey) surveys of galaxies in dense environments, spanning a redshift range 0.8<z~2x10^10^M_{sun}_), 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 Hubble Space Telescope/Wide Field Camera 3 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.

Cone search capability for table J/MNRAS/500/358/table1 (Galaxy clusters and groups in the GOGREEN and GCLASS samples)

Cone search capability for table J/MNRAS/500/358/clusters (Data associated with each system (Table 2))

Cone search capability for table J/MNRAS/500/358/zcat (Redshift catalogue (Table 4))

Cone search capability for table J/MNRAS/500/358/photo (Selected photometric data for each cluster system in the GCLASS, GOGREEN samples, COMOS UltraVISTA (v1.4; Muzzin+ 2013, J/ApJS/206/8), and SXDF SPLASH (v1.6; Mehta+ 2018, J/ApJS/235/36) fields (Table 3))