Probing the reheating temperature at colliders and with primordial nucleosynthesis

Considering gravitino dark matter scenarios with a long-lived charged slepton, we show that collider measurements of the slepton mass and its lifetime can probe not only the gravitino mass but also the post-inflationary reheating temperature T-R. In a model independent way, we derive upper limits on T-R and discuss them in light of the constraints from the primordial catalysis of Li-6 through bound-state effects. In the collider-friendly region of slepton masses below 1 TeV, the obtained conservative estimate of the maximum reheating temperature is about T-R = 3 x 10(9) GeV for the limiting case of a small gluino-slepton mass splitting and about T-R = 10(8) GeV for the case that is typical for universal soft supersymmetry breaking parameters at the scale of grand unification. We find that a determination of the gluino-slepton mass ratio at the Large Hadron Collider will test the possibility of T-R > 10(9) GeV and thereby the viability of thermal leptogenesis with hierarchical heavy right-handed Majorana neutrinos. (C) 2008 Elsevier B.V. All rights reserved.