Revealing atmospheric structures, clouds and chemistry of brown dwarfs and free-floating planetary mass objects

Spectral inversion techniques, also known as atmospheric retrievals, were first developed for remote sensing the Earth's atmospheric conditions, and have now been applied to Solar system planets, exoplanets and brown dwarfs. In this project you will use Ben Burningham's atmospheric retrieval framework ("Brewster": http://adsabs.harvard.edu/abs/2017MNRAS.470.1177B) to estimate atmospheric structure, chemistry and cloud properties of brown dwarfs, isolated planetary mass objects and planetary mass companions to stars. The results of this will then be used to test predictions from fully self-consistent radiative-convective equilibrium models and identify shortcomings in our understanding of the atmospheric physics of giant exoplanets and brown dwarfs. There is scope for the student to identify new lines of enquiry; however, promising examples include: testing for departures from chemical equilibrium and evaluating disequilibrium effects as a function of gravity; revealing cloud properties such as condensate species, cloud structure, particle sizes; testing predictions for thermal structure across a range of temperatures. These projects will initially exploit archival data, but new data will extend to new data sets as they become available. Atmospheric retrievals using Brewster will also play a key role in analysing data from the James Webb Space Telescope (JWST) following its launch in spring 2021.