Seminars at FGG

Probing the atmosphere of an extrasolar planet with HARPS-N

Speaker: Valerio Nascimbeni (Universit√° di Padova, INAF-OAPD)

Date and time: 2015-09-22 11:30

The characterisation of exoplanetary atmospheres is the path we have to follow to understand whether planets of our solar system, and in particular Earth-like planets, are the exception or the standard in our Universe. We are going to perform high resolution transmission spectroscopy in the region of the sodium doublet of the atmosphere of the Hot Jupiter HD209458b. The sodium lines, resolved ten times better than the state of the art for this target thanks to HARPS-N, contain an unprecedented amount of information which can drive us towards understanding of the physical conditions at the surface of the planet. In particular, we will measure: the temperature profile of the atmosphere (through the shape of the lines), super-rotation of the atmosphere (through the broadening of the line profiles), high altitude winds (through the blue-shift of the lines). In synthesis, we are going to exploit the unique HARPS-N performances and our theoretical expertise to constrain the atmosphere of this target better than ever done before.