English

SQuIGG$\vec{L}$E Survey: Massive z$\sim$0.6 Post-Starburst Galaxies Exhibit Flat Age Gradients

Astrophysics of Galaxies 2020-12-23 v1

Abstract

We present Gemini GMOS IFU observations of six massive (M1011 MM_\star\geq10^{11} \ M_\odot) A-star dominated post-starburst galaxies at z0.6z\sim0.6. These galaxies are a subsample of the SQuIGGL\vec{L}E Survey, which selects intermediate-redshift post-starbursts from the Sloan Digital Sky Survey spectroscopic sample (DR14) with spectral shapes that indicate they have recently shut off their primary epoch of star formation. Using HδAH\delta_A absorption as a proxy for stellar age, we constrain five of the galaxies to have young (600\sim 600 Myr) light-weighted ages at all radii and find that the sample on average has flat age gradients. We examine the spatial distribution of mass-weighted properties by fitting our profiles with a toy model including a young, centrally concentrated burst superimposed on an older, extended population. We find that galaxies with flat HδAH\delta_A profiles are inconsistent with formation via a central secondary starburst. This implies that the mechanism responsible for shutting off this dominant episode of star formation must have done so uniformly throughout the galaxy.

Keywords

Cite

@article{arxiv.2010.04734,
  title  = {SQuIGG$\vec{L}$E Survey: Massive z$\sim$0.6 Post-Starburst Galaxies Exhibit Flat Age Gradients},
  author = {David J. Setton and Rachel Bezanson and Katherine A. Suess and Qiana Hunt and Jenny E. Greene and Mariska Kriek and Justin S. Spilker and Robert Feldmann and Desika Narayanan},
  journal= {arXiv preprint arXiv:2010.04734},
  year   = {2020}
}

Comments

19 pages, 13 figures, resubmitting to ApJ following referee report, comments welcome. Key results in Figures 5 and 8