Säm Krucker (UCB) - Hard X-ray Observations as Diagnostics of Particle Acceleration in Solar

Time……… Wednesday, Oct 29th, 4:00 - 5:15 pm Where……  Room 415, North Physics Building Speaker…   Säm Krucker,  UC Berkeley and University of Applied Sciences Northwestern Switzerland. Title………  Hard X-ray Observations as Diagnostics of Particle Acceleration in Solar Flares  

Abstract: In the corona, Hard X-ray and gamma-ray observations reveal that as much as half of the released energy goes into particle acceleration. The acceleration mechanisms that provide these efficient conversions of magnetic energy into supra-thermal particles are currently not understood. In the past years however, significant progress has been made on the observational side; thanks in particular to observations by Reuven Ramaty High Energy Spectroscopic Imager (RHESSI), a NASA small explorer mission. After an extensive introduction, I will review recent observational results obtained by RHESSI. Furthermore, I will briefly describe future instrumentation such as the X-ray instrument STIX on board ESA’s Solar Orbiter mission and a sounding rocket experiment called FOXSI that successfully used hard X-ray focusing optics for solar observations.