Affiliation: Saint Mary’s University

Contribution: Poster

Title: From UV to Visible Light: Unveiling the Secrets of Galaxy Size Evolution in the CLAUDS+HSC Survey

Abstract: Galaxy scaling relations and their observed evolution are the key tests for models of galaxy assembly. State-of-the-art deep and large-area photometric surveys provide unprecedentedly tight constraints for the size-stellar mass relation over the redshift interval that covers most of the cosmic history. I will present a study of the changes in this scaling relation since z~1 we have carried on using 250,000 massive star-forming and quiescent galaxies in ultra-deep CFHT and Subaru imaging (~27 in ugrizy, CLAUDS+HSC survey). Following the pilot study (George et al. 2024, MNRAS, 528, 4797), we perform this analysis over the largest survey area (~20 sq.deg.) at two rest-frame wavelengths, ~3000 and ~5000 angstroms. Our study reveals an inside-out growth scenario, with both star-forming and quiescent galaxies exhibiting greater extension in UV than in visible light. We observe a deceleration in the size growth rate of star-forming galaxies in comparison with higher redshift observations, driven by the emergence and growth of their bulges. We further utilize the area and depth of the survey to explore the size of quiescent galaxies as a function of their environment with a sample of 250 rich clusters containing 3000 massive (log M>10.5) quiescent galaxies at z<1. Cluster galaxies are smaller than their field counterparts at all redshifts except at z~0. I will discuss physical processes contributing to this well-constrained observed size difference.

This contribution can be found at the Poster Hall.