The nature of superluminous supernovae (SLSNe), supernovae whose radiated luminosities are a hundred times greater than normal core collapse supernova events, remains an outstanding question in the transient field. Many models for their production have been postulated, although placing constraints upon these models via the properties of the explosions themselves remains challenging. The potential to unlock their progenitor types may be contained within the properties of their host galaxies. Prior studies have shown SLSNe to preferentially occur within faint, star forming galaxies, highly suggestive of a strong connection between progenitor production and environment conditions. Within this thesis I study the photometric characteristics of a sample of SLSN host galaxies, with a particular focus upon their stellar masses, metallicities and star forming properties. To do this I utilise high resolution imaging of a sample of SLSN host galaxies obtained with the Wide Field Camera 3 on the Hubble Space Telescope to study the global, and sub-galactic environments of SLSN events. By considering the photometric properties of these host galaxies within the near infrared and at rest-frame UV wavelengths, I am effectively able to probe the stellar mass and star forming properties of these environments. When compared to the host galaxies of other well-known core collapse transients, such as long gamma ray bursts and core collapse supernovae, constraints may be placed upon the likely progenitors of SLSNe relative to other transient progenitors. I show that on a global scale, the host galaxies of SLSNe are fainter, more compact, lower mass and less star forming than other core collapse transient host galaxies, which is highly indicative of low metallicity environments. I also highlight the diversity in environments exhibited between different spectral subclasses of SLSNe, which itself is reflective of the likely different progenitor routes for the two different subclasses of event. When considered on a sub-galactic scale, SLSNe events are associated with star forming regions within their galaxies, although at present it remains unclear whether these events are linked with the strongest regions of star formation (which would imply younger, more massive progenitors). Finally, I consider the issue of progenitor metallicity threshold estimations, and the consequences of using both global spectroscopic measurements and mass metallicity relation proxies to determine upper limits to progenitor chemical enrichment. I present a robust model for estimating this, incorporating the key sources of scatter in metallicity estimation which may be applied to a host galaxy populations to determine the presence of a threshold within the progenitor population.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:731374 |
| Date | January 2017 |
| Creators | Angus, Charlotte R. |
| Publisher | University of Warwick |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://wrap.warwick.ac.uk/95533/ |
Page generated in 0.0019 seconds