The Population of Double White Dwarfs

Double white dwarfs are a leading candidate progenitor population of thermonuclear supernovae. Understanding their role in the production of supernovae requires understanding their formation and evolution. The aim of this thesis is to do so through the observational study of double white dwarfs in our Galaxy. A combined approach will be taken using in depth photometric and spectroscopic studies of specific systems which have properties suited to accurate characterisation, such as eclipsing double white dwarfs, along with a more population focussed approach centred on the unrivalled database from the Gaia astrometric satellite. Timing studies will be pursued as a means to ultra-precise characterisation and to probe for second order effects such as mass transfer, tides and the presence of third-bodies. Population studies will focus on the use of Gaia to select potential double white dwarfs along with their later spectroscopic and photometric follow-up. Wide-field photometric archives such as the Zwicky Transient Facility and TESS will be used to test for photometric variability of the population of double white dwarfs.