Proton decay testing low energy SUSY

We show that gauge coupling unification in supersymmetry (SUSY) models can make a nontrivial interconnection between collider and proton decay experiments. Under the assumption of precise gauge coupling unification in the Minimal Supersymmeric Standard Model, with negligible grand unified theories threshold corrections, the low energy SUSY spectrum and the unification scale are intertwined, and the lower bound on the proton lifetime can be translated into upper bounds on SUSY masses. We find that the current limit on τ(P→π0e+) already excludes gluinos heavier than ∼70 (120 and 200) TeV if their mass ratio to winos, R≡M3/M2, is ∼1 (3 and 7), respectively. Next generation nucleon decay experiments are expected to bring these upper bounds down to ∼5 (10 and 15) TeV for R∼1 (3 and 7).