Higgsino dark matter in a supergravity model with nonuniversal gaugino masses

Abstract

We study a specific SUGRA model with nonuniversal gaugino masses as an alternative to the minimal SUGRA model in the context of supersymmetric dark matter. The lightest supersymmetric particle in this model comes out to be a Higgsino dominated instead of a bino dominated lightest neutralino. The thermal relic density of this Higgsino dark matter is somewhat lower than the cosmologically favoured range, which means it may be only a subdominant component of the cold dark matter. Nonetheless, it predicts favourable rates of indirect detection, which can be seen in square-km size neutrino telescopes.

Probing light higgsinos in natural SUSY from monojet signals at the LHC

“…In this case, the spin-independent neutralino-proton scattering cross section σ SI p must be re-scaled by a factor Ωχ0 1 h 2 /Ω PL h 2 [66,67], where Ω PL h 2 is the relic density measured by Planck satellite [68]. However, it should be mentioned that, if the naturalness requirement is relaxed, the heavy higgsino-like neutralino with a mass about 1 TeV can solely produce the correct relic density in the MSSM [69,70]. Of course, all these analyses are performed by assuming a standard ΛCDM model.…”

Theoretical direct WIMP detection rates for transitions to the first excited state inKr83

“…Some claims have recently been made, however, to the effect that the WMAP relic abundance constraint can be satisfied in the hyperbolic branch of the allowed SUSY parameter space, even though the neutralino is then primarily a higgsino [33]. We will not restrict ourselves to supersymmetry and we will adopt the optimistic view that the detection rates due to the spin may be large enough to be exploited by the experiments, see, e.g., [30,34,35] . Such a view is further encouraged by the fact that, unlike the scalar interaction, the axial current allows one to populate excited nuclear states, provided that their energies are sufficiently low so that they are accessible by the low energy LSP, a prospect proposed long time ago [36] and considered in some detail by Ejiri and collaborators [37].…”

Mixed neutralino dark matter in nonuniversal gaugino mass models

“…SUGRA models with nonuniversal gaugino masses at the GUT scale have been studied in many earlier works [13][14][15][16][17][18][19][20][21]. We shall only summarize the main results here, focusing on the simplest and most predictive GUT group, SU(5).…”