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arXiv · 0809.1953

511 keV $γ$-ray emission from the galactic bulge by MeV millicharged dark matter

Ji-Haeng Huh·Jihn E. Kim·Jong-Chul Park·Seong Chan Park
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Abstract

We propose a possible explanation for the recently observed anomalous 511 keV line with a new "millicharged" fermion. This new fermion is light [${\cal O}({\rm MeV})$]. Nevertheless, it has never been observed by any collider experiments by virtue of its tiny electromagnetic charge $εe$. In particular, we constrain parameters of this millicharged particle if the 511 keV cosmic $γ$-ray emission from the galactic bulge is due to positron production from this new particle.

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Ji-Haeng Huh, Jihn E. Kim, Jong-Chul Park, Seong Chan Park. 2008-09-11. 511 keV $γ$-ray emission from the galactic bulge by MeV millicharged dark matter. https://doi.org/10.1063/1.3052025

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