Split supersymmetry under GUT and current dark matter constraints

Abstract

We recalculate the two-loop beta functions for three gauge couplings taking into account all low energy threshold corrections in split supersymmetry (split-SUSY) which assumes a very high scalar mass scale (Formula presented.). We find that in split-SUSY with a gaugino mass unification assumption and with a large (Formula presented.) the gauge coupling unification requires a lower bound on the gaugino mass. Combined with the constraints from the dark matter relic density and direct detection limits, we find that split-SUSY is very restricted and for dark matter mass below 1 TeV the allowed parameter space can be fully covered by XENON-1T(2017).