Leptophobic dark matter at neutrino factories

High-luminosity fixed-target neutrino experiments present a new opportunity to search for light sub-GeV dark matter and associated new forces. We analyze the physics reach of these experiments to light leptophobic dark states coupled to the Standard Model via gauging the U(1)B baryon current. When the baryonic vector is light, and can decay to dark matter, we find that the MiniBooNE experiment in its current beam-dump configuration can extend sensitivity to the baryonic fine structure constant down to αB∼10-6. This is significantly below the existing limits over much of the sub-GeV mass range currently inaccessible to direct detection experiments.