Speaker:
Dr. Jeongwoo Lee Center for Solar-terrestrial Research, NJIT. Candidate for faculty position in Observational Solar Physics

Title:
"The physical relationship between microwave and hard X-ray bursts during solar flares"

Abstract:
Hard X-ray and microwave bursts are major diagnostics for understanding nonthermal electron acceleration during solar flares. They are conventionally considered as emitted by the same electron population and thus complement to each other. However, subtle differences between hard X-ray and microwave bursts do exist, which offers new insights into the electron kinetic process. This talk will present several recent developments in this area, including transport effects in the presence of inhomogeneous magnetic fields and anisotropic electron momentum distributions in injection, as measured by relative spectra and locations of microwave and hard X-ray sources. It will be shown that the classical paradigm called trap-and-precipitation systems is still a useful framework for understanding the relative differences in microwave and hard X-ray bursts. However, a new appreciation for the importance of anisotropic electron distributions demands a revision of the tools used to interpret the observations, and theoretical ideas on the electron acceleration mechanisms.

Host:
Dana Longcope