Cosmological evolution of scalar fields and gravitino dark matter in gauge mediation at low reheating temperatures

TL;DR

This paper explores how scalar field dynamics in gauge-mediated supersymmetry breaking models can produce gravitino dark matter at low reheating temperatures, aligning with cosmological and collider constraints.

Contribution

It demonstrates that gravitino dark matter can be generated at reheating temperatures below 10 GeV within a metastable gauge mediation framework, considering the scalar field's dynamics.

Findings

Gravitino density is highly sensitive to hidden sector parameters.

Low reheating temperatures can still produce the observed dark matter density.

Compatibility with LHC and BBN constraints is achieved at T_R < 10 GeV.

Abstract

We consider the dynamics of the supersymmetry-breaking scalar field and the production of dark matter gravitinos via its decay in a gauge-mediated supersymmetry breaking model with metastable vacuum. We find that the scalar field amplitude and gravitino density are extremely sensitive to the parameters of the hidden sector. For the case of an O'Raifeartaigh sector, we show that the observed dark matter density can be explained by gravitinos even for low reheating temperatures T_{R} < 10 GeV. Such low reheating temperatures may be implied by detection of the NLSP at the LHC if its thermal freeze-out density is in conflict with BBN.