Ejecta Distributions of Heavy Elements in the Cygnus Loop

Abstract

Abstract We analyzed the metal distribution of the Cygnus Loop using 14 and 7 pointing observation data obtained by the Suzaku and XMM-Newton observatories, respectively. The spectral analysis shows that all of the spectra are well fitted by a two-$kT_{\rm e}$ nonequilibrium ionization plasma model, as shown by earlier observations. From the best-fit parameters of the high-$kT_{\rm e}$ component, we calculated the emission measures about various elements, and showed the metal distribution of the ejecta component. We found that the distributions of Si and Fe are centered south of the geometric center toward the blow-out region. From the best-fit parameters, we also estimated the progenitor mass of the Cygnus Loop from our field of view (FOV) and the metal-rich region with a radius of 25$^\prime$ from the metal center. The result obtained from the metal circle is similar to that obtained from our entire FOV, which suggests a mixing of the metal. From the results, the mass of the progenitor star was estimated at 12-15$M_{\odot}$.