A Multiwavelength Dynamical State Analysis of ACT-CL J0019.6+0336

TL;DR

This study uses multiwavelength data to analyze the dynamical state of galaxy cluster ACT-CL J0019.6+0336, revealing signs of merging activity and complex morphology through X-ray, optical, and radio observations.

Contribution

It provides a comprehensive multiwavelength analysis combining X-ray, optical, and radio data to characterize the dynamical state of the galaxy cluster, highlighting its merging nature.

Findings

Detected disturbances in X-ray and optical morphology parameters.

Identified a significant BCG velocity offset indicating dynamical activity.

Discrepancies between mass estimates suggest a post-merging phase.

Abstract

In our study, we show a multiwavelength view of ACT-CL J0019.6+0336 (which hosts a radio halo), to investigate the cluster dynamics, morphology, and ICM. We use a combination of XMM-Newton images, Dark Energy Survey (DES) imaging and photometry, SDSS spectroscopic information, and 1.16 GHz MeerKAT data to study the cluster properties. Various X-ray and optical morphology parameters are calculated to investigate the level of disturbance. We find disturbances in two X-ray parameters and the optical density map shows elongated and axisymmetric structures with the main cluster component southeast of the cluster centre and another component northwest of the cluster centre. We also find a BCG offset of $\sim$950 km/s from the mean velocity of the cluster, and a discrepancy between the SZ mass, X-ray mass, and dynamical mass ($M_{X,500}$ and $M_{SZ,500}$ lies >3 $\sigma$ away from $M_{\rm{dyn},500}$), showing that J0019 is a merging cluster and probably in a post-merging phase.