Probing the Reheating Temperature at Colliders and with Primordial Nucleosynthesis

TL;DR

This paper demonstrates how collider measurements of slepton properties can indirectly determine the reheating temperature after inflation, linking collider physics with early universe cosmology and primordial element formation.

Contribution

It introduces a model-independent method to constrain the reheating temperature using collider data on sleptons and discusses implications for thermal leptogenesis.

Findings

Maximum reheating temperature estimated at 3×10^9 GeV for small gluino-slepton mass splitting.

Reheating temperature limit around 10^8 GeV for typical universal SUSY parameters.

Gluino-slepton mass ratio measurement at LHC can test high reheating temperature scenarios.

Abstract

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 TR. In a model independent way, we derive upper limits on TR and discuss them in light of the constraints from the primordial catalysis of lithium-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 TR=3\times 10^9 GeV for the limiting case of a small gluino-slepton mass splitting and about TR=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 TR>10^9 GeV and thereby the viability of thermal leptogenesis with hierarchical heavy right-handed Majorana neutrinos.