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arXiv · 1905.03431

Angular distribution of gamma-ray emission from velocity-dependent dark matter annihilation in subhalos

Kimberly K. Boddy·Jason Kumar·Jack Runburg·Louis E. Strigari
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Abstract

We consider the effect of velocity-dependent dark matter annihilation on the angular distribution of gamma rays produced in dark matter subhalos. We assume that the dark matter potential is spherically symmetric, characterized by a scale radius and scale density, and the velocity distribution is isotropic. We find that the effect of velocity-dependent dark matter annihilation is largely determined by dimensional analysis; the angular size of gamma-ray emission from an individual subhalo is rescaled by a factor which depends on the form of the dark matter distribution, but not on the halo parameters, while the relative normalization of the gamma-ray flux from different mass subhalos is rescaled by a factor which depends on the halo parameters, but not on the form of the dark matter distribution. We apply our results to a Navarro-Frenk-White profile for the case of an individual subhalo and comment on the application of these results to a distribution of subhalos.

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Kimberly K. Boddy, Jason Kumar, Jack Runburg, Louis E. Strigari. 2019-09-27. Angular distribution of gamma-ray emission from velocity-dependent dark matter annihilation in subhalos. https://doi.org/10.1103/physrevd.100.063019

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