Impact of internal bremsstrahlung on the detection of gamma-rays from neutralinos

TL;DR

This paper investigates how internal bremsstrahlung photons affect gamma-ray signals from neutralino dark matter annihilation, finding that while they can enhance fluxes, the impact on detection prospects remains limited.

Contribution

It provides a detailed analysis of internal bremsstrahlung effects in supersymmetric models and assesses their significance for gamma-ray dark matter searches.

Findings

Internal bremsstrahlung affects flux calculations mainly where line signals dominate.

In most scenarios, including bremsstrahlung does not significantly alter detection prospects.

Expected gamma-ray fluxes remain below current instrument sensitivities.

Abstract

We present a detailed study of the effect of internal bremsstrahlung photons in the context of the minimal supersymmetric standard models and their impact on gamma-ray dark matter annihilation searches. We find that although this effect has to be included for the correct evaluation of fluxes of high energy photons from neutralino annihilation, its contribution is relevant only in models and at energies where the lines contribution is dominant over the secondary photons. Therefore, we find that the most optimistic supersymmetric scenarios for dark matter detection do not change significantly when including the internal bremsstrahlung. As an example, we review the gamma-ray dark matter detection prospects of the Draco dwarf spheroidal galaxy for the MAGIC stereoscopic system and the CTA project. Though the flux of high energy photons is enhanced by an order of magnitude in some regions of the parameter space, the expected fluxes are still much below the sensitivity of the instruments.