A high-energy investigation of activity on potential planet hosts.

Low mass stars make up nearly 75% of the stellar population making them the most common potential planetary hosts. They are in the focus of  ongoing and planned surveys for habitable planet, since the distance of  the habitable zone to the star decreases with decreasing stellar temperature and therefore the stellar mass. But due to extremely low luminosities of  low mass stars the habitable zone moves closer to the star making the  orbiting world extremely vulnerable to the effects of magnetic activity and  the high energy emission from its host. Additionally, stellar activity is  also an important obstacle in planet search surveys. To address this, I have characterised the low mass stars to disentangle radial velocity variation due to activity from the planetary companion. Magnetic activity in low mass stars is a widely observed phenomenon which manifests itself in features such as spots, flares and high-energy coronal emission. Active low mass stars are capable of producing flares of short as well as longer durations. As the most common  potential planetary hosts, it is essential to understand the properties of  flaring plasma, how frequently and powerful these flares, etc. Do the giant  planet enhance the magnetic activity of their host star ? How do the planetary  atmosphere behave in the high energy environment of an active host ? These  are currently the key questions in extrasolar planetary science. In this talk, I will summarise the results and future prospects of my study on the coronal  activity/high energy emission of nearby low mass stars, which can potentially  host exoplanetary systems.