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arXiv · 2204.09364

High resolution X-ray study of supernova remnant J0453.6$-$6829 with unusually high forbidden-to-resonance ratio

Yosuke Koshiba·Hiroyuki Uchida·Takaaki Tanaka·Yuki Amano·Hidetoshi Sano·Takeshi Go Tsuru
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Abstract

Recent high-resolution X-ray spectroscopy has revealed that several supernova remnants (SNRs) in the Large Magellanic Cloud (LMC) show unusually high forbidden-to-resonance ($f/r$) line ratios. While their origin is still uncertain and debated, most of these SNRs have asymmetric morphology and/or show evidence of interaction with dense material, which may hint at the true nature of the anomalous $f/r$ ratios. Here we report on a detailed spectral analysis of an LMC SNR J0453.6$-$6829 with the Reflection Grating Spectrometer (RGS) onboard XMM-Newton. We find that the $f/r$ ratio of O$~$VII ($=1.06^{+0.09}_{-0.10}$) is significantly higher than expected from the previously-reported thermal model. The spectrum is fairly explained by taking into account a charge exchange (CX) emission in addition to the thermal component. Analyzing archival ATCA & Parkes radio data, we also reveal that H$~$I cloud is possibly interacting with J0453.6$-$6829. These results support the presence of CX in J0453.6$-$6829, as the origin of the obtained high $f/r$ ratio. Although a contribution of the resonance scattering (RS) cannot be ruled out at this time, we conclude that CX seems more likely than RS considering the relatively symmetric morphology of this remnant.

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Yosuke Koshiba, Hiroyuki Uchida, Takaaki Tanaka, Yuki Amano, Hidetoshi Sano, Takeshi Go Tsuru. 2022-04-20. High resolution X-ray study of supernova remnant J0453.6$-$6829 with unusually high forbidden-to-resonance ratio. https://doi.org/10.1093/pasj%2Fpsac033

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