Cluster-centric trends in bar size and pattern speed: the case of Abell 2199
Abstract
We investigate how the environment of a dynamically unrelaxed galaxy cluster influences the structure and dynamics of stellar bars. In particular, we examine cluster-centric variations in normalised bar size and bar pattern speed in Abell 2199. Our analysis is based on 578 spectroscopically confirmed members of Abell 2199, including a master sample of 325 galaxies with homogeneous stellar mass and star formation rate measurements. We identify 39 barred galaxies and measure their structural properties using isophotal ellipse fitting and three-component (bulge+disc+bar) photometric decompositions. For 22 barred galaxies with MaNGA integral-field spectroscopy, we estimate bar pattern speeds using the Tremaine-Weinberg method, obtaining robust measurements for 12 galaxies. Stellar population age and projected specific angular momentum are analysed using and from the MaNGA Pipe3D catalogue. Abell2199 exhibits star formation-density and morphology-density relations despite its non-relaxed dynamical state. Early-type spiral (ETS) barred galaxies show systematic cluster-centric variations in normalised bar size, with relatively larger bars towards the cluster centre and smaller bars at intermediate radii. A corresponding variation in bar pattern speed with cluster-centric distance is also observed. These trends motivate a division at 0.5, within which morphology-dependent environmental signatures become clearer, as barred galaxies in the inner region tend to host older stellar populations and lower projected angular momentum than those in the outskirts, with ETS+Bar galaxies retaining higher angular momentum compared to S0+Bar galaxies at comparable radii.
Cite
@article{arxiv.2605.28758,
title = {Cluster-centric trends in bar size and pattern speed: the case of Abell 2199},
author = {Chandan Watts and Sudhanshu Barway and Mousumi Das and Ewa L. Lokas},
journal= {arXiv preprint arXiv:2605.28758},
year = {2026}
}
Comments
14 pages, 14 figures, 3 tables. Accepted for publication in A&A