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arXiv · 2103.15384

Fermi-LAT detection of GeV $\gamma$-ray emission from Type Ia supernova remnant G272.2-3.2

Yun-Chuan Xiang·Ze-Jun Jiang
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Abstract

A new $\gamma$-ray source with a significance level of approximately 5$\sigma$ was reported in the region of SNR G272.2-3.2, analysing the approximately 12.4 years of observation data from the Fermi Large Area Telescope (Fermi-LAT). Its $\gamma$-ray spatial distribution did not show extended feature, and it had a soft spectrum with the spectral index of 2.56$\pm$0.01 of a power-law model. No significant variability of its light curve (LC) with 10 time bins was identified, and its spatial positions in the X-ray and GeV bands overlapped. We suggest that the new $\gamma$-ray source is a likely counterpart of SNR G272.2-3.2. Analysing its spectrum, we discussed the likely origins of the $\gamma$-ray emission.

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Yun-Chuan Xiang, Ze-Jun Jiang. 2021-03-29. Fermi-LAT detection of GeV $\gamma$-ray emission from Type Ia supernova remnant G272.2-3.2. https://doi.org/10.3847/1538-4357%2Fac0fe4

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