The JWST view of the barred galaxy population in the SMACS0723 galaxy cluster

TL;DR

This study uses JWST observations to analyze the distribution and evolution of barred galaxies in the SMACS0723 cluster at z=0.39, revealing environmental effects on bar formation dependent on galaxy mass.

Contribution

First analysis of bar fraction in a galaxy cluster at intermediate redshift using JWST data, highlighting environmental influences on bar formation across different galaxy masses.

Findings

Bar fraction depends on galaxy mass and environment.

Low-mass cluster galaxies show fewer bars compared to field galaxies.

High-mass cluster galaxies have a slightly lower bar fraction than in local clusters.

Abstract

The cosmic evolution of the barred galaxy population provides key information about the secular evolution of galaxies and the settling of rotationally dominated discs. We study the bar fraction in the SMACSJ0723.37323 (SMACS0723) cluster of galaxies at z = 0.39 using the Early Release Observations obtained with the NIRCam instrument mounted on the JWST telescope. As already found in nearby galaxy samples, we find that the bar fraction distribution of SMACS0723 is a strong function of the galaxy stellar luminosity/mass. The analogy with local clusters, such as Virgo and Coma, reveals a similar distribution among the three clusters for low-mass galaxies (log(M_star/M_sun) \leq 9.5). The comparison with a sample of local galaxies in a field environment shows a remarkable lack of bars in this low-mass regime for the SMACS0723 cluster (and therefore in Virgo and Coma) with respect to the field. At high masses (log(M_star/M_sun) \geq 10.25), galaxies in SMACS0723 show a slightly lower bar fraction than those in Coma. Our results support a scenario where cluster environment affects the formation of bars in a mass-dependent way. At high masses, the mild increase in the bar fraction of local clusters (Coma) with respect to both SMACS0723 and local field galaxies suggests a weak effect of cluster environment possibly triggering bar formation. On the other hand, low-mass galaxies show the same bar fraction in the three clusters (different redshifts) and a significant drop with respect to field galaxies at z=0, therefore suggesting that: i) the bar fraction of low-mass galaxies in clusters is not evolving during the last 4~Gyr, and ii) bar formation is severely inhibited in low-mass galaxies living in clusters (Abridged).