Indirect and direct detection prospect for TeV dark matter in the nine parameter MSSM

We investigate the prospects of indirect and direct dark matter searches within the minimal supersymmetric standard model with nine parameters (MSSM-9). These nine parameters include three gaugino masses, Higgs, slepton and squark masses, all treated independently. We perform a Bayesian Monte Carlo scan of the parameter space taking into consideration all available particle physics constraints such as the Higgs mass of 126 GeV, upper limits on the scattering cross section from direct-detection experiments, and assuming that the MSSM-9 provides all the dark matter abundance through a thermal freeze-out mechanism. Within this framework we find the two most probable regions for dark matter: 1-TeV Higgsino-like and 3-TeV Wino-like neutralinos. We discuss prospects for future indirect [in particular the Cherenkov Telescope Array (CTA)] and direct detection experiments. We find that for slightly contracted dark matter profiles in our Galaxy, which can be caused by the effects of baryonic infall in the Galactic center, CTA will be able to probe a large fraction of the remaining allowed region in synergy with future direct detection experiments like XENON-1T.

Figure 1

The contours represent 68% and 95% posterior probability credible regions. Colored points reproduce all the experimental observables within $2\sigma$ of confidence level. The cyan diamond represent the pure Higgsino case from [13, 21], and the blue triangle the pure Wino case from [69]. The color coding indicates the branching fraction into $W^{+}{W}^{-}$ final states. The green lines show the sensitivity of CTA as derived in Ref. [43] for $\overline{b}b$ final states and 100h observation time (assuming 1% systematics). The purple lines show the H.E.S.S. Galactic center limits for generic hadronic final states [70], adopting an Einasto (solid), a contracted NFW (dotted), and a shallow NFW (dashed) profiles. The brown dotted line shows the Fermi-LAT limit from the analysis of the dwarf spheroidal galaxies [71]. The CTA and Fermi-LAT limits correspond to ${\chi }_1^0{\chi }_1^0\to b\overline{b}$, but limits for $W^{+}{W}^{-}$ final states are very similar.

Figure 2

The same as Fig. 1, but for annihilation into monochromatic photons. The cyan diamond represent the pure Higgsino case from [13, 21], and the blue triangle the pure Wino case [18]. Colors indicate the Higgsino fraction of the lightest neutralino. The green lines show the line sensitivity of CTA as derived from [73], while purple lines are the H.E.S.S. limits [74], all for the Galactic center.

Figure 3

Similar to Fig. 1, but showing the total annihilation cross section against the WIMP-proton spin-independent cross section. The blue triangle and the cyan arrow are the theoretical values of the pure Wino and pure Higgsino case from Refs. [84, 85]. The arrow indicates that the value of ${\sigma }_p^{\mathrm{SI}}$ is a theoretical upper limit. The color coding indicates the Higgsino fraction. Green lines show the sensitivity of CTA for Einasto (solid) and contracted NFW (dotted) profiles for the Galactic center [43]. Cyan and pink lines represent LUX limit [27] and XENON-1T sensitivity [35]. Both the limit and sensitivity lines assume $m_{{\chi }_1^0}=1\mathrm{TeV}$. CTA sensitivity lines correspond to ${\chi }_1^0{\chi }_1^0\to b\overline{b}$.