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DOE OSTI · 1834158

Contribution from TeV halos to the isotropic gamma-ray background

Xu, Fei·Hooper, Dan
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Abstract

We report 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. We also calculate the contribution from TeV halos to the isotropic gamma-ray background, finding that these sources should contribute significantly to this flux at the highest measured energies, constituting up to ~20 % of the signal observed above ~0.1TeV. We also comment on the implications of our results for the origin of the diffuse neutrino flux detected by IceCube.

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79 ASTRONOMY AND ASTROPHYSICSgamma ray astronomyneutron starspulsars

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Xu, Fei, Hooper, Dan. 2022-07-05. Contribution from TeV halos to the isotropic gamma-ray background. https://doi.org/10.1103/physrevd.106.023005

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