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arXiv · 2609.34155

Comment on "Fermi-LAT Galactic Center Excess Morphology of Dark Matter in Simulations of the Milky Way Galaxy"

Kevork N. Abazajian·Jason Kumar·Oscar Macias
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Abstract

Muru et al. [Phys. Rev. Lett. 135, 161005 (2025)] conclude from the HESTIA constrained simulations that the $γ$-ray morphologies of the Galactic Center Excess predicted by dark matter annihilation and by an old stellar population are essentially indistinguishable. Their "quadratic dark matter" maps, however, show the square of the mass projected along the line of sight, $\bigl[\intρ\,s^{2}\,ds\bigr]^{2}$, rather than the annihilation integral $\intρ^{2}\,ds$. Squaring a nonnegative map preserves its isophote shapes at corresponding intensity levels, as confirmed by the reported contour axis ratios. The corrected calculation on the same simulations does not support their conclusion.

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Kevork N. Abazajian, Jason Kumar, Oscar Macias. 2026-09-28. Comment on "Fermi-LAT Galactic Center Excess Morphology of Dark Matter in Simulations of the Milky Way Galaxy". https://arxiv.org/abs/2609.34155

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