Light Higgsino as the tail of the μ-Bμ solution

Gauge mediation predicts 10 TeV or heavier squarks because such a heavy stop is required to explain the observed 125 GeV Higgs boson mass without a large trilinear soft mass term in the minimal supersymmetric standard model. Although such a high scale cannot be searched by the LHC directly, gauge mediation also predicts a hierarchy μ2,Bμ by a simple and naive solution of the μ problem. We point out that this simple and naive way of generating the μ (Bμ) term works in the case of 10 TeV or heavier squarks with a slight breaking of a grand unified theory relation among messenger B-terms. Furthermore, the upper bound on the Higgsino mass is obtained from the observed Higgs boson mass, perturbativity of a relevant coupling, and a condition avoiding tachyonic sneutrinos and stop. It turns out that the light Higgsino of O(100) GeV is a promising signal of gauge mediation.