Comparing Galactic Center MSSM dark matter solutions to the Reticulum II gamma-ray data

Abstract

Observations with the Fermi Large Area Telescope (LAT) indicate a possible small photon signal originating from the dwarf galaxy Reticulum II that exceeds the expected background between 2 GeV and 10 GeV. We have investigated two specific scenarios for annihilating WIMP dark matter within the phenomenological Minimal Supersymmetric Standard Model (pMSSM) framework as a possible source for these photons. We find that the same parameter ranges in pMSSM as reported by an earlier paper to be consistent with the Galactic center excess, is also consistent with the excess observed in Reticulum II, resulting in a J-factor of $\log_{10}(J(\alpha_{int}=0.5 deg)) \simeq (20.3-20.5)^{+0.2}_{-0.3}$. This J-factor is consistent with $\log_{10}(J(\alpha_{int}=0.5 deg)) = 19.5^{+1.0}_{-0.6}$ GeV$^2$cm$^{-5}$, which is derived using an optimized spherical Jeans analysis of kinematic data obtained from the Michigan/Magellan Fiber System (M2FS).