Wednesday 30 Nov 2016: The atmospheres of irradiated brown dwarfs
Dr. Sarah Casewell - University of Leicester
Physics, 4th Floor 14:00-15:00
Brown dwarfs are often thought of as failed stars, falling into the mass gap between hydrogen burning stars, and exoplanets. In this seminar, I will discuss brown dwarfs in close orbits with evolved stars, their formation, evolution, and how the brown dwarf's atmosphere is ultimately affected by the constant irradiation from its host star. These systems are rare, both in part due to the brown dwarf desert, but also due to an evolution mechanism which has a high chance of the brown dwarf being accreted onto the core of a RGB or AGB star. However, the brown dwarfs that survive this evolution are left in close, tidally locked orbits, which provides an ideal laboratory with which to study irradiation of cool atmospheres. They often have large temperature differences between their day and night-sides, similar to hot exoplanets, and as they are directly observable, may allow us to unlock some of the mysteries of exoplanet atmospheres.