JWST NIRCam Observations of the Globular Cluster Population of RXJ 2129.7+0005

TL;DR

This study uses JWST NIRCam imaging to analyze the distribution and properties of globular clusters in a galaxy cluster at redshift 0.234, revealing their spatial distribution, color-magnitude characteristics, and concentration patterns.

Contribution

First detailed JWST NIRCam analysis of globular cluster populations in a galaxy cluster at this redshift, providing insights into their distribution and properties.

Findings

Identified 3,160 globular cluster candidates brighter than F150W=29.5.

Globular clusters follow a radial power-law distribution with index 1.58.

Redder GCs are more centrally concentrated and spatially elliptical.

Abstract

We present an analysis of the globular cluster (GC) population in the galaxy cluster RXJ 2129.7+0005 (z = 0.234) based on JWST NIRCam imaging in three filters: F115W, F150W, and F200W. We use this material to provide a detailed look at the color-magnitude distribution of the GCs and their spatial distribution around the central giant galaxy. We identified 3,160 GC candidates brighter than F150W=29.5, and assessed photometric completeness through artificial star tests. We determined that the GCs follow a radial power-law distribution with an index of $1.58 \pm 0.04$, with the redder GCs exhibiting a slightly greater central concentration. Their spatial distribution is also highly elliptical, closely following the shape of the BCG halo light.