Likelihood analysis of supersymmetric SU(5) GUTs

We perform a likelihood analysis of the constraints from accelerator experiments and astrophysical observations on supersymmetric (SUSY) models with SU(5) boundary conditions on soft SUSY-breaking parameters at the GUT scale. The parameter space of the models studied has seven parameters: a universal gaugino mass m$_{1/2}$, distinct masses for the scalar partners of matter fermions in five- and ten-dimensional representations of SU(5), m$_5$ and m$_{10}$, and for the 5 and $\bar{5}$ Higgs representations m$_{{H}_{u}}$ and m$_{{H}_{d}}$ , a universal trilinear soft SUSY-breaking parameter A$_0$, and the ratio of Higgs vevs tanβ. In addition to previous constraints from direct sparticle searches, low-energy and flavour observables, we incorporate constraints based on preliminary results from 13 TeV LHC searches for jets + $E\!\!\!/_T$events and long-lived particles, as well as the latest PandaX-II and LUX searches for direct Dark Matter detection. In addition to previously identified mechanisms for bringing the supersymmetric relic density into the range allowed by cosmology, we identify a novel $\tilde{u}_{R}/\tilde{c}_{R} − \tilde{χ}^{0}_1$ coannihilation mechanism that appears in the supersymmetric SU(5) GUT model and discuss the role of $\tilde{\nu}_\tau$ coannihilation. We find complementarity between the prospects for direct Dark Matter detection and SUSY searches at the LHC