Hard X-ray emission from a flare-related jet

Hazel Bain (University of Glasgow)

Thursday 10 April 2008, 15:45, Room 604, Kelvin Building

We report the first observations of hard X-ray emission from a flare-related jet. The event occurred on the 22nd of August 2002 and its evolution was observed by a number of instruments. In particular we study the pre-impulsive and impulsive phase of the flare using data from RHESSI and the TRACE 195 passband. During this period RHESSI observes significant hard X-ray emission to energies as high as 50 keV in the jet. Estimates from RHESSI spectroscopy suggest a temperature of the order ~20MK for this time. Radio observations from the Nobeyama Radioheliograph (NoRH) show a positive spectral index for the ejected material backing the presence of non-thermal emission. This also shows the jet to be optically thick at radio frequencies, possibly due to free-free absorption.