Dark Matter Interpretation of the Fermi-LAT Galactic Center Excess

Alan Lu

doi:10.54097/exd0v680

Authors

Alan Lu

DOI:

https://doi.org/10.54097/exd0v680

Keywords:

Galactic Center Excess (GCE); dark matter (DM); Fermi-LAT.

Abstract

In this work, we analyze the γ-ray Galactic Center Excess (GCE) as a potential signal from dark matter (DM) annihilation. Using updated annihilation spectra, we calculate the gammaray flux for various annihilation channels and compare the results to those obtained from previous analyses of Fermi-LAT data. We assume generalized Navarro-Frenk-White (gNFW) and Einasto DM density profiles, from which we estimate the geometrical factor . We determine the best-fit DM mass and annihilation cross section for each channel, with the b quark, Z boson, and W boson channels yielding the most favorable results. The b quark channel provides a good match with a DM mass around 45–60 GeV and a cross section near the thermal relic value. These findings reinforce the viability of the DM annihilation scenario for the GCE, and we present spectra and cross section comparisons that strengthen this interpretation.

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References

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