| How can stellar winds affect atmospheric escape in close-in exoplanets? |
| Aline A. Vidotto |
|
Trinity College Dublin
Ireland |
| As the wind outflows from a star, it permeates the interplanetary medium, interacting with any planet it encounters. In this talk I will present some of our recent works on how winds of low-mass stars can affect surrounding exoplanets. In particular, I will concentrate on close-in exoplanets, whose atmospheres are highly irradiated. Stellar high-energy radiation (X-ray and extreme ultraviolet, XUV) drives atmospheric escape in close-in exoplanets. While XUV radiation powers escape in close-in exoplanets, the winds of the host stars, due to their strong pressures, can confine planetary atmospheres, reducing or even preventing their escape. In some close-in exoplanets, thus, XUV radiation and stellar winds are competing processes in the Physics of atmospheric escape. I will discuss the effects of stellar winds on the atmospheres of exoplanets and how they affect transit signatures in hydrogen lines and, potentially, in helium lines as well. |