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Information × Registration Number 0223U005569, 0123U103014 , R & D reports Title Study of the inside and outside medium properties of the Cassiopeia A supernova remnant by using radio interferometers popup.stage_title Head Stanyslavskyi Lev O., Registration Date 25-12-2023 Organization Radio Astronomical Institute of the National Academy of Sciences of Ukraine popup.description2  The results of experimental studies of Cassiopeia A and Cygnus A radio emission at the GURT, URAN-2 radio telescopes were obtained. The directivity diagrams of the GURT and URAN-2 antenna arrays were installed in the zenith position, and due to the diurnal rotation of the Earth, the investigated sources of radio emission were observed in the source transit mode. Based on data sets from each radio telescope, integral radio spectra were obtained and properties of the medium inside and outside the remnant were determined, including temperature, average ionization level, and ionized gas emission rate. Absorption parameters were analyzed using the Mann-Kendell test for the presence of a trend. It is established which of the parameters have or don't have a trend. The calculated change of parameters in the trend for a three-month period. According to the results of the analysis of the changes in the parameters in the trend, the presence of certain macroscopic changes in the remnant of supernova Cassiopeia A was confirmed, namely, an increase in the optical depth of the shockless emission by almost 40% in three months, with small changes in the values of the emission rate, the average number of ions, and the temperature of the electrons of the medium inside the remnant. In addition, broadband radio spectroscopic studies of the medium lying in the line of sight in the direction of the Cassiopeia A supernova remnant (SNN) were carried out using the URAN-2 radio telescope. The obtained results confirm the theoretical assumption of the influence of the age-related decrease in the flux density of Cassiopeia A on the width of the studied carbon radio recombination lines, in particular, changes in the contribution of radiative broadening to the total width of these lines. Product Description popup.authors Yevhen V. Vasylkivskyi popup.nrat_date 2023-12-25 Close