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arXiv · 2603.05457

A likelihood analysis for gamma-ray background models

Chance Hoskinson·Jason Kumar·Pearl Sandick
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Abstract

Indirect searches for dark matter using dwarf spheroidal galaxies are limited by systematic uncertainties in modeling diffuse gamma-ray backgrounds. We present a likelihood-based comparison of locally constructed empirical background models and theoretically-motivated models that incorporate the Fermi-LAT diffuse background. The empirical models we study include both an independent-binning approach and a covariance-based approach that captures cross-energy correlations. Using ensembles of blank-sky regions and information criteria which account for model complexity, we find that empirical background descriptions provide a statistically competitive fit to gamma-ray data on degree scales in high-latitude regions.

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Chance Hoskinson, Jason Kumar, Pearl Sandick. 2026-03-05. A likelihood analysis for gamma-ray background models. https://arxiv.org/abs/2603.05457

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