Impact of Inert Higgsino Dark Matter

Abstract

We consider a recently proposed supersymmetric radiative seesaw model which is coupled with the minimal supergravity. The conventional R parity and $Z_2$ invariance are imposed, which ensures the existence of a multi-component dark matter system. We assume that the pair of the lightest neutralino $\tildeχ$ and the fermionic component $\tildeξ$ of the inert Higgs supermultiplet is dark matter. If $\tildeξ$ is lighter than $\tildeχ$, and the lightest neutral inert Higgs boson is kinematically forbidden to decay (third dark matter), the allowed region in the $m_0{\rm \mathchar`-}M_{1/2}$ plane increases considerably, where $m_0$ and $M_{1/2}$ are the universal soft-supersymmetry-breaking scalar and gaugino mass, respectively, although the dominant component of the multi-component dark matter system is $\tildeχ$. There is a wide allowed region above the recent LHC limit.