On the Origin of Light Dark Matter Species
  TeV-mass dark matter charged under a new GeV-scale gauge force can explain
electronic cosmic-ray anomalies. We propose that the CoGeNT and DAMA direct
detection experiments are observing scattering of light stable states --
"GeV-Matter" -- that are charged under this force and constitute a small
fraction of the dark matter halo. Dark higgsinos in a supersymmetric dark
sector are natural candidates for GeV-Matter that scatter off protons with a
universal cross-section of 5 x 10^{-38} cm^2 and can naturally be split by
10-30 keV so that their dominant interaction with protons is down-scattering.
As an example, down-scattering of an O(5) GeV dark higgsino can simultaneously
explain the spectra observed by both CoGeNT and DAMA. The event rates in these
experiments correspond to a GeV-Matter abundance of 0.2-1% of the halo mass
density. This abundance can arise directly from thermal freeze-out at weak
coupling, or from the late decay of an unstable TeV-scale WIMP. Our proposal
can be tested by searches for exotics in the BaBar and Belle datasets.
