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arXiv · 2408.04611

Tools for probing new physics with newly discovered gamma-ray targets

Chance Hoskinson·Jason Kumar·Pearl Sandick
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Abstract

We present a computational tool, TweedleDEE, for empirically modeling diffuse gamma-ray background emission in a 1 degree region of the sky, using publicly available gamma-ray data off-axis from the region of interest. This background model allows a user to perform a purely data-driven search for anomalous localized sources of gamma-ray emission, including new physics. A major application of this tool would be in searching for dark matter annihilation in newly discovered astrophysical targets. For this purpose, we derive a scaling relation for determining velocity-dependent $J$-factors using only the stellar parameters, which can be broadly applied to obtain dark matter constraints from new targets. As an application of these tools, we use TweedleDEE and MADHATv2 to perform the first search for dark matter annihilation in the newly discovered Leo VI dwarf spheroidal galaxy, and present model constraints for a variety of choices of the annihilation channel and velocity dependence of the cross section.

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Chance Hoskinson, Jason Kumar, Pearl Sandick. 2024-08-08. Tools for probing new physics with newly discovered gamma-ray targets. https://arxiv.org/abs/2408.04611

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