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تسجيل مستخدم جديدAn analysis of the possible thermal emission at radio frequencies from an evolved supernova remnant HB 3 (G132.7 + 1.3): revisited
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It has recently been reported that some of the flux density values for an evolved supernova remnant (SNR) HB 3 (G132.7 + 1.3) are not accurate. In this work we revised an analysis of the possible thermal emission at radio frequencies from the SNR HB 3 using the recently published, corrected, flux density values. A model including a sum of non-thermal (purely synchrotron) and thermal (bremsstrahlung) component is applied for fitting integrated radio spectrum of the SNR. The contribution of thermal component in total volume emissivity at $1 mathrm{GHz}$ was estimated to be $approx37 %$. The ambient density was also estimated to be $napprox 9 mathrm{cm}^{-3}$ for the $mathrm{T}=10^{4} mathrm{K}$. Again, we obtained the relatively significant presence of thermal emission at radio frequencies from the SNR so we could support interaction between SNR HB 3 and adjacent molecular cloud associated with the H {sc ii} region W3. Our model estimates for thermal component contribution to total volume emissivity at $1 mathrm{GHz}$ and ambient density are similar to those obtained earlier ($approx40 %$, $approx10 mathrm{cm^{-3}}$). It is clear that the corrected flux density values do not change the basic conclusions.
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