Determination of the far-infrared properties of galaxies in the Coma cluster
This thesis presents results from the deepest ever far-infrared study of the Coma cluster (Abell 1656), with the Herschel PACS and SPIRE instruments being used to observe the cluster at a wavelength range of 70-500 _m. These observations resulted in a catalogue consisting of 70 galaxies which were spectroscopically confirmed as Coma cluster members, from which far-infrared galaxy luminosity functions at 70, 100 and 160 _m were constructed. Additionally, the far-infrared properties of 68 of these galaxies were determined from spectral energy distribution fits across the full wavelength range. Finally, these galaxies were grouped by morphological type, resulting in 30 elliptical galaxies, 37 spiral galaxies and one with an unknown morphology. These results were then compared to other studies of both clusters and the field in order to ascertain the extent to which environmental processes affect galaxy evolution. A comparison of the luminosity functions at 100 and 160 _m and the equivalent functions from the Herschel Virgo cluster survey Auld et al. (2013) showed similarities in both the functional form and the function parameters describing them. A further comparison of the Coma cluster luminosity functions at all three PACS wavelengths and various field galaxy luminosity functions was made, and again the forms and function parameters were consistent to within the errors. This would imply that the environmental processes thought to occur within the clusters do not have as great an effect on the galaxy population as initially thought. The far-infrared properties derived from the spectral energy distribution fits were analysed by galaxy type. The early-types were found to have mean normalised dust masses, dust temperatures and total infrared luminosities of log10 _ Mdust Mstellar =
Networked Digital Library of Theses and Dissertations