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arXiv · 1702.05266

Searching for Gamma-Ray Emission from Reticulum II by Fermi-LAT

Yi Zhao·Xiao-Jun Bi·Peng-Fei Yin·Xin-Min Zhang
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Abstract

Recently, many new dwarf spheroidal satellites (dSphs) have been discovered by the Dark Energy Survey (DES). These dSphs are ideal candidates for probing for gamma-ray emissions from dark matter (DM) annihilation. However, no significant signature has been found by the Fermi-LAT dSph observations. In this work, we reanalyze the Fermi-LAT Pass 8 data from the direction of Reticulum II, where a slight excess has been reported by some previous studies. We treat Reticulum II (DES J0335.6-5403) as a spatially extended source, and and that no significant gamma-ray signature is observed. Based on this result, we set upper-limits on the DM annihilation cross section.

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Yi Zhao, Xiao-Jun Bi, Peng-Fei Yin, Xin-Min Zhang. 2018-02-13. Searching for Gamma-Ray Emission from Reticulum II by Fermi-LAT. https://doi.org/10.1088/1674-1137%2F42%2F2%2F025102

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