A large-scale approach to modelling Biosignatures: First Steps

For this poster I will be presenting the approaches taken to produce synthetic spectra for molecules believed to be biosignatures. In astrochemistry, biosignatures describe a group of molecules which could be produced by life and therefore act as an indication of it. Naturally, by being able to identify these molecules it will be possible to screen exoplanets for the possibility of harbouring life. 

Recently, Seager, Bains and Petkowski (2016) produced a catalogue of possible biosignatures, which totalled above 14,000 molecules. There are groups such as the ExoMol group which model these molecules at extremely high precision. However, due to the large number of molecules, a high precision method would take an unreasonable amount of time and therefore a faster means of producing spectra is required. The work shown within is designed to be quick and produce data for the full rovibronic spectrum rather than selected bands. I will show that anharmonic corrections are needed to be able to simulate qualitatively correct ro-vibrational transitions. In my method, this is done by implementing TOSH, transition optimised shifted hermites, which was first detailed by Lin, Gilbert and Gill (2007). Finally I will be presenting my latest results using this analytical anharmonic approach.