X-ray study of the supernova remnant G337.2−0.7

Abstract

Abstract This paper reports on the Suzaku result of the Galactic supernova remnant (SNR) G337.2−0.7. The X-ray spectrum is well explained by three components in ionizing phase. One is a plasma with a low temperature $kT = 0.70_{-0.03}^{+0.02}\:$keV, solar abundances, and an ionization parameter $n_{\rm e}t = 5.7^{+0.7}_{-0.4}\times 10^{11}\:$s cm−3. The second is a middle-temperature plasma with $kT = 1.54^{+0.13}_{-0.02}\:$keV and high metal abundances in a highly ionized state of $n_{\rm e}t = 3.6^{+0.2}_{-0.5}\times 10^{11}\:$s cm−3, and the third is a high-temperature plasma with $kT = 3.1^{+0.2}_{-0.1}\:$keV and high metal abundances in a low-ionized state of $n_{\rm e}t=2.1^{+0.4}_{-0.2}\times 10^{10}\:$s cm−3. The high metal-abundance plasmas are likely to be of an ejecta origin, while the solar abundance plasma would be of an interstellar-gas origin. The abundance pattern and mass of the ejecta confirm that G337.2−0.7 is a remnant of a Type Ia supernova (SN). The derived Fe mass of ejecta MFe = 0.025–0.039 M⊙ is far smaller than that expected from any Type Ia model, suggesting that most Fe has not yet been heated by the reverse shock. The ejecta has enhanced distribution in the northeastern region compared to the central region, and therefore the SN explosion or SNR evolution would be asymmetric.