Energy Distribution of Electrons Producing Microwave 1966 Impulsive Bursts and X-Ray Bursts from the Sun

Abstract

Abstract The energy distribution of high energy electrons which emit gyro-synchrotron radiation as microwave impulsive bursts is computed as a function of time for some plausible initial distribution functions. The theoretical decay curves of the radio emission from these electrons are compared with observed decay curves of the radio bursts to deduce the initial energy distribution. The most probable initial distribution may be the power law K–γ, with γ of 5 to 3. Other energy distributions give too long decay times for the radio emissions. A comprehensive model of radio and hard X-ray bursts (>20 kev) is proposed. A major part of high energy electrons is trapped in a region invisible at the radio frequencies. This region may be the source of hard X-ray bursts. On the other hand, a small fraction, of the other of 10–3 ~ 10–4, of the high energy electrons is trapped in an outer region and contributes to the microwave impulsive burst.