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arXiv · 2111.03646

The Contribution From TeV Halos to the Isotropic Gamma-Ray Background

Fei Xu·Dan Hooper
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Abstract

Recent observations have shown that pulsars are surrounded by extended regions which emit TeV-scale gamma rays through the inverse Compton scattering of very high energy electrons and positrons. Such TeV halos are responsible for a large fraction of the Milky Way's TeV-scale gamma-ray emission. In this paper, we calculate the gamma-ray spectrum from the population of TeV halos located within the Andromeda Galaxy, predicting a signal that is expected to be detectable by the Cherenkov Telescope Array (CTA). We also calculate the contribution from TeV halos to the isotropic gamma-ray background (IGRB), finding that these sources should contribute significantly to this flux at the highest measured energies, constituting up to $\sim 20\%$ of the signal observed above $\sim 0.1 \, {\rm TeV}$.

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Fei Xu, Dan Hooper. 2021-11-05. The Contribution From TeV Halos to the Isotropic Gamma-Ray Background. https://doi.org/10.1103/physrevd.106.023005

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