Electroweak resummation of neutralino dark-matter annihilation into high-energy photons

TL;DR

This paper performs electroweak resummation for neutralino dark matter annihilation into high-energy photons, revealing significant reductions in photon yield that impact MSSM parameter constraints.

Contribution

It extends electroweak resummation techniques to general neutralino models, quantifying the effect on photon yields for TeV-scale dark matter.

Findings

Photon yield reduces by about 20% for Higgsino-like neutralinos at 1 TeV.

Photon yield reduces by up to 45% for wino-like neutralinos near 3 TeV.

Resummation effects are crucial for accurate MSSM dark matter constraints.

Abstract

We consider the resummation of large electroweak Sudakov logarithms for the annihilation of neutralino DM with $\mathcal{O}$(TeV) mass to high-energy photons in the minimal supersymmetric standard model, extending previous work on the minimal wino and Higgsino models. We find that NLL resummation reduces the yield of photons by about $20\%$ for Higgsino-dominated DM at masses around 1~TeV, and up to $45\%$ for neutralinos with larger wino admixture at heavier masses near 3~TeV. This sizable effect is relevant when observations or exclusion limits are translated into MSSM parameter-space constraints.