Runaway Discharge in a Magnetized Plasma and Generation of High Energy Radiation

University Of Maryland, College Park, College Park MD

Investigators

Abstract

The investigators will study the self-focusing of whistler waves in magnetized plasmas and their interaction with relativistic electrons in a runaway discharge, and the generation of high-energy radiation (X-rays and gamma-rays). These studies are motivated by the recent satellite observations of gamma-rays emanating from the mesosphere, a puzzle whose solution requires a new understanding of the plasma processes in the mesosphere during lightning discharges. The numerical models of runaway discharge will be developed that deal with runaway beams generated by a broadband pulse in the presence of magnetic field. It relies on the runaway of magnetized relativistic electrons. In this model, an ionization driven self-focusing instability which self-consistently maintains the runaway population, and channels the energy of whistler waves along field-aligned filaments is the key element. The approach is based on an innovative concept of whistler mediated electron discharge and will develop a new understanding of self-focusing of waves in magnetized plasmas and its relationship to relativistic electrons. This research will enhance technological understanding related to the development of tunable X-ray and gamma-ray sources, and the potential impacts of gamma-ray flashes on aviation electronics. The project will train undergraduate students and will target participation by students from underrepresented minority groups. The research results will be widely disseminated through publication in scientific journals and web pages.