Probing MeV Dark Matter at Low--Energy $e^{+}{e}^{-}$ Colliders

Natalia Borodatchenkova, Debajyoti Choudhury, Manuel Drees

It has been suggested that the annihilation of Dark Matter particles χwith mass between 0.5 and 20 MeV into e^+e^- pairs could be responsible for the excess flux of 511 keV photons…