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Completing the X-ray view of the recently discovered supernova remnant G53.41+0.03

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 نشر من قبل Vladim\\'ir Dom\\v{c}ek
 تاريخ النشر 2021
  مجال البحث فيزياء
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Aims: We present a detailed X-ray study of the recently discovered supernova remnant (SNR) G53.41+0.03 that follows up and further expands on the previous, limited analysis of archival data covering a small portion of the SNR. Methods: With the new dedicated 70ks XMM-Newton observation we investigate the morphological structure of the SNR in X-rays, search for a presence of a young neutron star and characterise the plasma conditions in the selected regions by means of spectral fitting. Results: The first full view of SNR G53.41+0.03 shows an X-ray emission region well aligned with the reported half-shell radio morphology. We find three distinct regions of the remnant that vary in brightness and hardness of the spectra, and are all best characterised by a hot plasma model in a non-equilibrium ionisation state. Of the three regions, the brightest one contains the most mature plasma, with ionisation age $tau approx 4times10^{10}$s cm$^{-3}$ (where $tau = n_e t$), a lower electron temperature of kT$_mathrm{e} approx 1$ keV and the highest estimated gas density of n$_mathrm{H}approx 0.87$ cm$^{-3}$. The second, fainter but spectrally harder, region reveals a younger plasma ($tau approx 1.7times10^{10}$s cm$^{-3}$) with higher temperature (kT$_mathrm{e} approx 2$ keV) and two to three times lower density (n$_mathrm{H}approx 0.34$ cm$^{-3}$). The third region is very faint, but we identify spectroscopically the presence of a hot plasma.Employing several methods for age estimation, we find the remnant to be $t approx 1000-5000$ yrs old, confirming the earlier reports of a relatively young age. The environment of the remnant also contains a number of point sources, of which most are expected to be positioned in the foreground. Of the two point sources in the geometrical centre of the remnant one is consistent with the characteristics of a young neutron star.

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