An investigation of the outskirts of the galaxy cluster XLSSC122
| dc.contributor.author | Lonsbrough, Bryn | |
| dc.contributor.supervisor | Willis, Jon | |
| dc.date.accessioned | 2025-08-27T21:08:16Z | |
| dc.date.available | 2025-08-27T21:08:16Z | |
| dc.date.issued | 2025 | |
| dc.degree.department | Department of Physics and Astronomy | |
| dc.degree.level | Master of Science MSc | |
| dc.description.abstract | I investigate the redshift 1.98 galaxy cluster XLSSC 122 using the Hubble Space Telescope (HST) from the core of the cluster out to 3 Mpc, a scale equivalent to 10 times the R500 = 295 kpc radius. I present an expanded photometric and spectroscopic catalogue of the cluster, bringing the total number of spectroscopically classified member galaxies to 74, with 35 new member galaxies added in the outer regions of the cluster. I compute the radial galaxy number density profiles in the cluster, and observe no clear evidence of infalling groups or cosmic filaments. I observe a clear bimodal colour relation in member galaxies, with an increasing number of red galaxies approaching the cluster centre. This red fraction enhancement, as well as the coincident appearance of post-starburst galaxies, indicates a rapid cessation of star formation as galaxies enter the cluster. We use a simple model to show that the observed galaxy properties may be explained by ram pressure stripping at or near the virial radius of the cluster. | |
| dc.description.scholarlevel | Graduate | |
| dc.identifier.uri | https://hdl.handle.net/1828/22659 | |
| dc.language | English | eng |
| dc.language.iso | en | |
| dc.rights | Available to the World Wide Web | |
| dc.subject | Galaxy clusters | |
| dc.subject | Galaxies | |
| dc.title | An investigation of the outskirts of the galaxy cluster XLSSC122 | |
| dc.type | Thesis |