Dartmouth Events

Physics & Astronomy - Cosmology Seminar - Dr. Yotam Soreq, MIT

Title: "Gamma Ray Constraints on Decaying Dark Matter and Implications for IceCube"

Thursday, October 5, 2017
1:15pm – 2:15pm
Wilder 202
Intended Audience(s): Public
Categories: Lectures & Seminars

Abstract: Utilizing the Fermi measurement of the gamma-ray spectrum toward the Galactic Center, we derive some of the strongest constraints to date on the dark matter (DM) lifetime in the mass range from hundreds of MeV to above an EeV.  We model Galactic and extragalactic DM decay and include contributions to the DM-induced gamma-ray flux resulting from both primary emission and inverse-Compton scattering of primary electrons and positrons. For the extragalactic flux, we also calculate the spectrum associated with cascades of high-energy gamma-rays scattering off of the cosmic background radiation. We argue that a decaying DM interpretation for the 10 TeV - 1 PeV neutrino flux observed by IceCube is disfavored by our constraints. Our results also challenge a decaying DM explanation of the AMS-02 positron flux. We interpret the results in terms of individual final states and in the context of simplified scenarios such as a hidden-sector glueball model.

For more information, contact:
Tressena Manning
603-646-2854

Events are free and open to the public unless otherwise noted.