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arXiv · 2212.06843

Central Concentration of Asymmetric Features in Post-starburst Galaxies at $z \sim 0.8$

Kazuharu G. Himoto·Masaru Kajisawa
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Abstract

We present morphological analyses of Post-starburst galaxies (PSBs) at $0.7 0.8$, while only 16% (2%) of quiescent (star-forming) galaxies show such high $C_{A}$ values. Those PSBs with high $C_{A}$ have relatively low overall asymmetry of $A \sim 0.1$, but show remarkable asymmetric features near the centre. The fraction of those PSBs with high $C_{A}$ increases with increasing SSFR in 321--1000 Myr before observation rather than residual on-going star formation. These results and their high surface stellar mass densities suggest that those galaxies experienced a nuclear starburst in the recent past, and processes that cause such starbursts could lead to the quenching of star formation through rapid gas consumption, supernova/AGN feedback, and so on.

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Kazuharu G. Himoto, Masaru Kajisawa. 2022-12-13. Central Concentration of Asymmetric Features in Post-starburst Galaxies at $z \sim 0.8$. https://doi.org/10.1093/mnras%2Fstac3687

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