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Arxiv: Unveiling Multiple Physical Processes on a Cluster Galaxy at z=0.3 Using JWST Published: 9/23/2024 7:59:25 PM Updated: 9/23/2024 7:59:25 PM

Paper abstract: We present a study of a previously identified candidate ``jellyfish'' galaxyin the Abell 2744 cluster, F0083, which showed faint signs of a tidalinteraction in archival imaging. We used publicly available, PSF-matched deepphotometric data from the Hubble and James Webb Space Telescopes, to infer thespatially-resolved star-formation history of this galaxy. F0083 shows clearsigns of ram-pressure stripping (RPS), with a recently enhanced star-formationrate (SFR) orientated towards the South-West quadrant of the stellar disc. Thestellar mass surface density is heavily asymmetric, with a variation of nearly1 dex between the Western spiral arm and the postulated tidal feature. Thisfeature appears to contain a high proportion of older stars, ruling out RPS asthe cause of this ``unwinding''. An investigation of nearby galaxies revealsthe most probable interaction candidate to be a compact elliptical galaxy,28171, of mass \log_{10}(M_*/\rm{M}_{\odot})=8.53\pm0.04 embedded in thetidal stream along our line-of-sight. The star-formation history of the tidalfeature indicates a steep change in SFR at lookback times t_L<~1\,Gyr.The most probable formation scenario of F0083 thus indicates a low-speedinteraction with 28171, followed by RPS as the combined system approachespericentre passage. Our results demonstrate the ability of photometric data todistinguish between these consecutive processes.