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arXiv · 2104.07676

From starburst to quiescence: post-starburst galaxies and their large-scale clustering over cosmic time

Aaron Wilkinson·Omar Almaini·Vivienne Wild·David Maltby·William G. Hartley·Chris Simpson·Kate Rowlands
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Abstract

We present the first study of the large-scale clustering of post-starburst (PSB) galaxies in the high redshift Universe ($0.5 10^{14}$M$_{\odot}$), suggesting they are likely to be infalling satellite galaxies in cluster-like environments. High-mass PSB galaxies are more weakly clustered at low redshifts, but they reside in higher mass haloes with increasing look-back time, suggesting strong redshift-dependent halo downsizing. These key results are consistent with previous results suggesting that two main channels are responsible for the rapid quenching of galaxies. While high-redshift ($z>1$) galaxies appear to be quenched by secular feedback mechanisms, processes associated with dense environments are likely to be the key driver of rapid quenching in the low-redshift Universe ($z<1$). Finally, we show that the clustering of photometrically selected PSBs are consistent with them being direct descendants of highly dust-enshrouded sub-millimetre galaxies (SMGs), providing tantalising evidence for the oft-speculated evolutionary pathway from starburst to quiescence.

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Aaron Wilkinson, Omar Almaini, Vivienne Wild, David Maltby, William G. Hartley, Chris Simpson, Kate Rowlands. 2021-04-15. From starburst to quiescence: post-starburst galaxies and their large-scale clustering over cosmic time. https://doi.org/10.1093/mnras/stab965

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