Search for dark matter gauge bosons with fixed target electron scattering
The cosmological standard model assumes that a large fraction of the universe is made of dark matter while only a small fraction of matter is made of ordinary baryonic matter. A particle physics candidate would appear naturally e.g. if one demands R-parity in Supersymmetry. Most experiments therefore concentrate on the direct detection of the so called "lightest supersymmetric particle" as candidate. A more general approach however was suggested by Arkani-Hamed et al., explaining a series of phenomena like e.g. the DAMA/LIBRA modulation and the positron excess detected by several cosmic ray experiments by a U(1) gauge boson of the dark matter sector which mixes with the photon. Such gauge bosons would have naturally a mass in the range of 1 GeV, making this accessible to existing accelerators, however with very small coupling. In this talk a first experiment for the search for light gauge bosons at the Mainz Microtron (MAMI) will be presented.