RT Journal Article
ID 316141154a037606
A1 Rutkevych, B. P.
A1 Melnik, V. N.
T1 PROPAGATION OF TYPE III SOLAR BURSTS RADIO EMISSION THROUGH THE CORONA. 1. TIME PROFILE
JF Radio Physics and Radio Astronomy
JO RPRA
YR 2012
FD 2012-08-13
VO 3
IS 3
SP 205
OP 213
K1 type III bursts
K1 radio frequency emission
K1 group velocity
K1 group delay
K1 time profile
AB The propagation of electromagnetic waves in the coronal plasma, from the area of generation toward an observer, is considered based on the generally accepted plasma theory of type III burst generation. Special attention is given to the increase in the group velocity of the electromagnetic waves, arising from the variation in the plasma density away from the Sun. An analytic formula for the wave's group velocity as function of the generation area coordinate and of separation from that has been derived. The formula is used to analyze the group delay of the waves within two models of the corona. Taking into account the spatial size of the electron beam, it has become possible to obtain representations for the time profile of the electromagnetic radiation. A fine-structured electron beam has been considered. The radiation profile from such a beam can be shown to resemble closely the observed profile of type III bursts with a fine structure. Also, a spherical beam of a monotonically increasing radius is considered, and the dynamic spectrum of type III bursts is derived. The burst duration has been evaluated over a broad frequency range.
PB Begell House
LK https://www.dl.begellhouse.com/journals/6fd1549c0e2c05da,4e9409a35a49a927,316141154a037606.html