A Morphological Analysis of the Galaxy Cluster XLSSC 122
| dc.contributor.author | Leste, Ophélie Karishma | |
| dc.contributor.supervisor | Willis, Jon | |
| dc.date.accessioned | 2023-08-24T17:48:47Z | |
| dc.date.available | 2023-08-24T17:48:47Z | |
| dc.date.copyright | 2023 | en_US |
| dc.date.issued | 2023-08-24 | |
| dc.degree.department | Department of Physics and Astronomy | en_US |
| dc.degree.level | Master of Science M.Sc. | en_US |
| dc.description.abstract | We present a morphological analysis of the 29 spectroscopically confirmed mem- bers of the most massive galaxy cluster at z ∼ 2, XLSSC 122. The cluster was dis- covered in the XMM Large Scale Structure survey as a faint, extended X-ray source and was later confirmed via a Sunyaev-Zel’dovich decrement along its line of sight. We perform photometry using Statmorph on images of the cluster members from the Hubble Space Telescope (HST) Wide Field Camera (WFC3) in the F140W and F105W bands. We perform visual assesment of the images, as well as non-parametric mor- phological analyses based on measurements such as the concentration C, asymmetry A, Gini and M20 to classify the cluster members as being bulge-dominated, disky or possible mergers. The properties of the XLSSC 122 members show clear evidence of bimodality. The bulge-dominated galaxies are redder, older and are found in the denser regions of the cluster, while the galaxies showing disturbed features are bluer, younger, and are found towards the outskirts of the cluster. XLSSC 122 is also found to be deficient of the blue and disturbed galaxy populations compared to galaxies from CANDELS/3D-HST field surveys. We further consider results from dark-matter only cosmological simulations presented in Cosmosim to derive the merger history of the members in cluster halos such as XLSSC 122 at the epoch of observation. The ana- lysis of the simulated data along with the morphological observations, suggest that the galaxy interactions that induce structural disturbances in the blue population of XLSSC 122 members occurred at redshifts in the range 2 < z < 3. This epoch is likely to indicate to the time prior to the infall of these galaxies into the virial radius of the cluster, where galaxy mergers and star formation are eventually suppressed, resulting in their evolution into bulge-dominated red-sequence galaxies. | en_US |
| dc.description.scholarlevel | Graduate | en_US |
| dc.identifier.uri | http://hdl.handle.net/1828/15284 | |
| dc.language | English | eng |
| dc.language.iso | en | en_US |
| dc.rights | Available to the World Wide Web | en_US |
| dc.subject | galaxy cluster | en_US |
| dc.subject | galaxy evolution | en_US |
| dc.subject | galaxy morphology | en_US |
| dc.subject | high redshift galaxy cluster | en_US |
| dc.title | A Morphological Analysis of the Galaxy Cluster XLSSC 122 | en_US |
| dc.type | Thesis | en_US |