RADIO SPECTRUM EVOLUTION OF THE SUPERNOVA REMNANT CASSIOPEIA A AT FREQUENCIES 35–65 MHZ

Abstract

The results of radio emission observations for Cassiopeia A source at frequencies 35, 38, 40, 45, 50, 55, 60 and 65 MHz are presented. At these frequencies, the radio-emission flux density ratio between Cassiopeia A and Cygnus A for the epoch of 2014 is obtained. Brief information about the antenna facility and reception equipment used in the measurements is given. At frequencies 35−65 MHz, the radio emission flux of Cassiopeia A is found for the epoch of 2014 by comparison with the well-known flux density of Cygnus A. The intersection frequency of the low-frequency spectra for Cassiopeia A and Cygnus A is experimentally determined. The results obtained by other authors for the secular decrease of the flux density of Cassiopeia A radio emission at 38 MHz are confirmed.

Keywords

• supernova remnant
• radio-wave radiation flux evolution
• cassiopeia a
• gurt