Gamma Rays from Bino-like Dark Matter in the MSSM

TL;DR

This paper explores bino-like neutralino dark matter in the MSSM, focusing on regions where annihilation produces monoenergetic photons, and assesses the observability of such signals.

Contribution

It identifies parameter space regions with significant monoenergetic photon production and evaluates their potential detectability in current experiments.

Findings

Branching fraction to monoenergetic photons can reach 1-10%.

Total cross section for observable signals is generally too small.

Regions with light sleptons and heavy squarks are of particular interest.

Abstract

We consider regions of the parameter space of the Minimal Supersymmetric Standard Model (MSSM) with bino-like neutralino dark matter in which a large fraction of the total dark matter annihilation cross section in the present era arises from annihilation to final states with monoenergetic photons. The region of interest is characterized by light sleptons and heavy squarks. We find that it is possible for the branching fraction to final states with monoenergetic photons to be comparable to that for continuum photons, but in those cases the total cross section will be so small that it is unlikely to be observable. For models where dark matter annihilation may be observable in the present era, the branching fraction to final states with monoenergetic photons is O(1-10%).