Exclusion of leptophilic dark matter models using XENON100 electronic recoil data

Abstract

Laboratory experiments searching for galactic dark matter particles scattering off nuclei have so far not been able to establish a discovery. We use data from the XENON100 experiment to search for dark matter interacting with electrons. With no evidence for a signal above the low background of our experiment, we exclude a variety of representative dark matter models that would induce electronic recoils. For axial-vector couplings to electrons, we exclude cross-sections above $6x10^{-35} cm^2$ for particle masses of $m_chi = 2 GeV/c^2$. Independent of the dark matter halo, we exclude leptophilic models as explanation for the long-standing DAMA/LIBRA signal, such as couplings to electrons through axial-vector interactions at a 4.4 sigma confidence level, mirror dark matter at 3.6 $\sigma$, and luminous dark matter at 4.6 $\sigma$.