The Velocity Dispersion Function for Massive Quiescent and Star-forming Galaxies at 0.6 < z ≤ 1.0

The Astrophysical Journal, vol. 939, pp. 90

Abstract

Abstract We present the first direct spectroscopic measurement of the stellar velocity dispersion function (VDF) for massive quiescent and star-forming galaxies at 0.6 < z ≤ 1.0. For this analysis we use individual measurements of stellar velocity dispersion from high-signal-to-noise-ratio spectra from the public Large Early Galaxy Astrophysics Census (LEGA-C) survey. We report a remarkable stability of the VDF for both quiescent and star-forming galaxies within this redshift range, though we note the presence of weak evolution in the number densities of star-forming galaxies. We compare both VDFs with previous direct and inferred measurements at local and intermediate redshifts, with the caveat that previous measurements of the VDF for star-forming galaxies are poorly constrained at all epochs. We emphasize that this work is the first to directly push to low stellar velocity dispersion (σ ⋆ > 100 km s−1) and extend to star-forming galaxies. We are largely consistent with the high-sigma tail measured from BOSS, and we find that the VDF remains constant from the median redshift of LEGA-C, z ∼ 0.8, to the present day.

Authors 13

1. Lance Taylor

   University of Pittsburgh

   Affiliation as printed

   Department of Physics and Astronomy and PITT PACC, University of Pittsburgh, Pittsburgh, PA 15260, USA

2. Rachel Bezanson

   University of Pittsburgh

   Affiliation as printed

   Department of Physics and Astronomy and PITT PACC, University of Pittsburgh, Pittsburgh, PA 15260, USA

3. Arjen van der Wel

   Ghent University

   Affiliation as printed

   Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, 9000 Gent, Belgium

4. Alan Pearl

   University of Pittsburgh

   Affiliation as printed

   Department of Physics and Astronomy and PITT PACC, University of Pittsburgh, Pittsburgh, PA 15260, USA

5. Eric F. Bell

   University of Michigan

   Affiliation as printed

   Department of Astronomy, University of Michigan, 1085 South University Ave., Ann Arbor, MI 48109, USA

6. Francesco D’Eugenio

   Ghent University

   Affiliation as printed

   Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, 9000 Gent, Belgium

7. Marijn Franx Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 AA Leiden, The Netherlands

8. Michael V. Maseda Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 AA Leiden, The Netherlands

9. Adam Muzzin

   York University

   Affiliation as printed

   Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, Ontario, M3J 1P3, Canada

10. David Sobral

    Lancaster University

    Affiliation as printed

    Department of Physics, Lancaster University, Lancaster LA1 4YB, UK

11. Caroline M. S. Straatman

    Ghent University

    Affiliation as printed

    Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, 9000 Gent, Belgium

12. Katherine E. Whitaker

    University of Copenhagen · University of Massachusetts Amherst

    Affiliation as printed

    Cosmic Dawn Center (DAWN), Copenhagen, Denmark

    Department of Astronomy, University of Massachusetts, Amherst, MA 01003, USA

13. Po-Feng Wu

    National Astronomical Observatory of Japan

    Affiliation as printed

    National Astronomical Observatory of Japan, Osawa 2-21-1, Mitaka, Tokyo 181-8588, Japan