SupersymmetricU(1)′model with multiple dark matters

Abstract

We consider a scenario where a supersymmetric model has multiple dark matter particles. Adding a $U(1{)}^{\ensuremath{'}}$ gauge symmetry is a well-motivated extension of the minimal supersymmetric standard model (MSSM). It can cure the problems of the MSSM such as the $\ensuremath{\mu}$ problem or the proton decay problem with high-dimensional lepton number and baryon number violating operators which $R$ parity allows. An extra parity ($U$ parity) may arise as a residual discrete symmetry after $U(1{)}^{\ensuremath{'}}$ gauge symmetry is spontaneously broken. The lightest $U$-parity particle (LUP) is stable under the new parity becoming a new dark matter candidate. Up to three massive particles can be stable in the presence of the $R$ parity and the $U$ parity. We numerically illustrate that multiple stable particles in our model can satisfy both constraints from the relic density and the direct detection, thus providing a specific scenario where a supersymmetric model has well-motivated multiple dark matters consistent with experimental constraints. The scenario provides new possibilities in the present and upcoming dark matter searches in the direct detection and collider experiments.