Properties of Type Ia Supernovae and application to Cosmology
Prof P. Mazzali, Prof. P. James & Dr D. Bersier.
Type Ia Supernovae are luminous stellar explosions which can be observed out to redshifts corresponding to a time when the Universe was half its present age. They have been instrumental in the discovery of the acceleration of the Universe and Dark Energy. Yet, little is known about their physical properties, and even the nature of their progenitors is hotly debated, although we should expect that it should have a direct impact on the observed light display of the SN.
The underlying theme of this project is to further our understanding of SNe Ia, their physics, and their application in Cosmology. The thesis can be developed according to the student's preferences. The student working on this topic will have access to a large database of SN data (light curves and spectra), as well as to radiation transport codes which can be used to model the data and extract physical information.
The student can take part in observational campaigns (telescopes on La Palma and in Chile, observations with HST) and work on the analysis of the data; investigate the properties of existing datasets, looking for trends that may have a physical significance (e.g. properties that depend on SN luminosity or on host galaxy type); perform detailed modelling of individual SNe in order to determine their properties with a high level of accuracy and confidence; compare observational results with the predictions of theoretical models; work on extending and improving existing codes and testing these new tools.
If for example there are different paths to make a SN Ia, this thesis should constitute a major step towards identifying which channels are possible, what are their observable manifestations, and which subgroups of SNe Ia can be ascribed to which particular channel. This would have a major impact on the confidence with which we use SNe Ia in Cosmology.