Multicomponent dark matter

Abstract

We explore multicomponent dark matter models where the dark sector consists of multiple stable states with different mass scales, and dark forces coupling these states further enrich the dynamics. The multicomponent nature of the dark matter naturally arises in supersymmetric models, where both $R$ parity and an additional symmetry, such as a ${Z}_{2}$, is preserved. We focus on a particular model where the heavier component of dark matter carries lepton number and annihilates mostly to leptons. The heavier component, which is essentially a sterile neutrino, naturally explains the PAMELA and synchrotron signals, without an excess in antiprotons, which typically mars other models of weak scale dark matter. The lighter component, which may have a mass from a GeV to a TeV, may explain the DAMA signal, and may be visible in low threshold runs of CDMS and XENON, which search for light dark matter.