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arXiv · 1009.5872

Observational evidences for the existence of 17.4 keV decaying degenerate sterile neutrinos near the Galactic Center

Man Ho Chan·Ming-Chung Chu
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Abstract

We show that the existence of a degenerate halo of sterile neutrinos with rest mass of 17.4 keV near the Galactic Center can account for both the excess 8.7 keV emission observed by the $Suzaku$ mission and the power needed ($10^{40}$ erg s$^{-1}$) to maintain the high temperature of the hot gas (8 keV) near the Galactic Center. The required decay rate and mixing angle of the sterile neutrinos are $Γ\ge 5 \times 10^{-20}$ s$^{-1}$ and $\sin^22 θ\sim 10^{-3}-10^{-4}$ respectively. These values are consistent with a low reheating temperature in the inflation model, and suggest the exciting possibility that the sterile - active neutrino oscillation can be visible in near future experiments.

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Man Ho Chan, Ming-Chung Chu. 2010-09-29. Observational evidences for the existence of 17.4 keV decaying degenerate sterile neutrinos near the Galactic Center. https://doi.org/10.1088/2041-8205%2F727%2F2%2Fl47

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