The Large Early Galaxy Astrophysics Census (LEGA-C) Data Release 2: Dynamical and Stellar Population Properties of z 1 Galaxies in the COSMOS Field uri icon

abstract

  • Abstract We present the second data release of the Large Early Galaxy Astrophysics Census (LEGA-C), an ESO 130night public spectroscopic survey conducted with VIMOS on the Very Large Telescope. We release 1988 spectra with typical continuum S/N20 1 of galaxies at 0.6z1.0, each observed for 20 hr and fully reduced with a custom-built pipeline. We also release a catalog with spectroscopic redshifts, emission-line fluxes, Lick/IDS indices, and observed stellar and gas velocity dispersions that are spatially integrated quantities, including both rotational motions and genuine dispersion. To illustrate the new parameter space in the intermediate-redshift regime probed by LEGA-C, we explore relationships between dynamical and stellar population properties. The star-forming galaxies typically have observed stellar velocity dispersions of 150 km s1 and strong H absorption (H A5 ), while passive galaxies have higher observed stellar velocity dispersions (200 km s1) and weak H absorption (H A0 ). Strong [O III]5007/H ratios tend to occur mostly for galaxies with weak H A or galaxies with higher observed velocity dispersion. Beyond these broad trends, we find a diversity of possible combinations of rest-frame colors, absorption-line strengths, and emission-line detections, illustrating the utility of spectroscopic measurements to more accurately understand galaxy evolution. By making the spectra and value-added catalogs publicly available we encourage the community to take advantage of this very substantial investment in telescope time provided by ESO.

published proceedings

  • The Astrophysical Journal Supplement Series

author list (cited authors)

  • Straatman, C., van der Wel, A., Bezanson, R., Pacifici, C., Gallazzi, A., Wu, P., ... Spilker, J. S.

complete list of authors

  • Straatman, Caroline MS||van der Wel, Arjen||Bezanson, Rachel||Pacifici, Camilla||Gallazzi, Anna||Wu, Po-Feng||Noeske, Kai||Barišić, Ivana||Bell, Eric F||Brammer, Gabriel B||Calhau, João||Chauke, Priscilla||Franx, Marijn||van Houdt, Josha||Labbé, Ivo||Maseda, Michael V||Muñoz-Mateos, Juan C||Muzzin, Adam||van de Sande, Jesse||Sobral, David||Spilker, Justin S

publication date

  • December 2018