Implications of Increased Central Mass Surface Densities for the Quenching of Low-mass Galaxies Academic Article uri icon

abstract

  • Abstract We use the Cosmic Assembly Deep Near-infrared Extragalactic Legacy Survey data to study the relationship between quenching and the stellar mass surface density within the central radius of 1 kpc (1) of low-mass galaxies (stellar mass M * 109.5 M ) at 0.5 z < 1.5. Our sample is mass complete down to 109 M at 0.5 z < 1.0. We compare the mean 1 of star-forming galaxies (SFGs) and quenched galaxies (QGs) at the same redshift and M *. We find that low-mass QGs have a higher 1 than low-mass SFGs, similar to galaxies above 1010 M . The difference of 1 between QGs and SFGs increases slightly with M * at M * 1010 M and decreases with M * at M * 1010 M . The turnover mass is consistent with the mass where quenching mechanisms transition from internal to environmental quenching. At 0.5 z < 1.0, we find that 1 of galaxies increases by about 0.25 dex in the green valley (i.e., the transition region from star forming to fully quenched), regardless of their M *. Using the observed specific star formation rate gradient in the literature as a constraint, we estimate that the quenching timescale (i.e., time spent in the transition) of low-mass galaxies is a few (4) Gyr at 0.5 z < 1.0. The mechanisms responsible for quenching need to gradually quench star formation in an outside-in way, i.e., preferentially ceasing star formation in outskirts of galaxies while maintaining their central star formation to increase 1. An interesting and intriguing result is the similarity of the growth of 1 in the green valley between low-mass and massive galaxies, which suggests that the role of internal processes in quenching low-mass galaxies is a question worthy of further investigation.

published proceedings

  • ASTROPHYSICAL JOURNAL

altmetric score

  • 7.33

author list (cited authors)

  • Guo, Y., Carleton, T., Bell, E. F., Chen, Z., Dekel, A., Faber, S. M., ... Perez-Gonzalez, P. G.

citation count

  • 3

complete list of authors

  • Guo, Yicheng||Carleton, Timothy||Bell, Eric F||Chen, Zhu||Dekel, Avishai||Faber, SM||Giavalisco, Mauro||Kocevski, Dale D||Koekemoer, Anton M||Koo, David C||Kurczynski, Peter||Lee, Seong-Kook||Liu, FS||Papovich, Casey||Perez-Gonzalez, Pablo G

publication date

  • June 2021