Thermal Dark Matter Below a MeV
نویسندگان
چکیده
منابع مشابه
MeV-mass dark matter and primordial nucleosynthesis
The annihilation of new dark matter candidates with masses mX in the MeV range may account for the galactic positrons that are required to explain the 511 keV γ-ray flux from the galactic bulge. We study the impact of MeV-mass thermal relic particles on the primordial synthesis of H, He, and Li. If the new particles are in thermal equilibrium with neutrinos during the nucleosynthesis epoch they...
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It has been suggested that the pair annihilation of dark matter particles chi with mass between 0.5 and 20 MeV into e+e- pairs could be responsible for the excess flux (detected by the INTEGRAL satellite) of 511 keV photons coming from the central region of our Galaxy. The simplest way to achieve the required cross section while respecting existing constraints is to introduce a new vector boson...
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The observed 511 keV emission from the galactic bulge could be due to very light (MeV) annihilating dark matter particles. To distinguish this hypothesis from conventional astrophysical sources, we study dwarf spheroidals in the region observed by the International Gamma-Ray Astrophysics Laboratory/SPI such as Sagittarius. As these galaxies have comparatively few stars, the prospects for 511 ke...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2018
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.120.021801