Wednesday 05 Nov 2014: Seminar: *11am* Investigating the inner regions of circumstellar discs and the DIANA project
Dr John Ilee - University of St Andrews
Physics, 4th floor 11:00-12:00
The inner regions of circumstellar discs play an important role in the accretion process of young stars. If the central star has a high luminosity, as is the case with sufficiently massive stars, then these regions of the disc can be heated to high temperatures (>1500 K). Such temperatures cause the sublimation of dust grains, and lead to an inner disc consisting only of gas. While investigation of these gaseous regions is essential in determining the accretion processes that occur within young stars, direct observation of them is difficult due to their small angular size. Therefore, there is much interest in determining indirect observational techniques that can probe these inner discs. In this talk, I will discuss how we have used a spectroscopic emission feature - the CO first overtone bandheads - to probe these regions in young stars of intermediate to high masses. I will then discuss how we are extending this investigation using the radiation-thermo-chemical disc modelling software ProDiMo, in order to discover more about the conditions within these inner gaseous discs. Finally, I will talk more generally about the work we are currently undertaking with the DIANA project - a European FP7 project aimed at detailed modelling of multi-wavelength observations of protoplanetary discs.