# Recently Quenched Galaxies at z = 0.2 - 4.8 in the COSMOS UltraVISTA Field

## TL;DR

This study analyzes recently-quenched galaxies across a broad redshift range, revealing their increasing number density over time and their role as transitional objects in galaxy evolution.

## Contribution

First comprehensive analysis of recently-quenched galaxies from z=0.2 to 4.8 using COSMOS data, highlighting their evolving properties and transitional role.

## Key findings

- Number density of RQGs increases with time at z>1.
- Low-mass RQGs grow rapidly at z<1.
- RQGs have intermediate morphology between star-forming and passive galaxies.

## Abstract

We present a new analysis of the stellar mass function and morphology of recently-quenched galaxies (RQGs), whose star formation has been recently quenched for some reason. The COSMOS2015 catalog was exploited to select those galaxies at 0.2 < z < 4.8, over 1.5 deg2 of the Cosmic Evolution Survey (COSMOS) UltraVISTA field. This is the first time that RQGs are consistently selected and studied in such a wide range of redshift. We find increasing number density of RQGs with time in a broad mass range at z>1, while low-mass RQGs start to grow very rapidly at z < 1. We also demonstrate that the migration of RQGs may largely drive the evolution of the stellar mass function of passive galaxies. Moreover, we find that the morphological type distribution of RQGs are intermediate between those of star-forming and passive galaxies. These results indicate that RQGs represent a major transitional phase of galaxy evolution, in which star-forming galaxies turn into passive galaxies, accompanied by the build up of spheroidal component.