Probing the Supersymmetric Inflaton and Dark Matter link via the CMB, LHC and XENON1T experiments

TL;DR

This paper explores the connection between supersymmetric inflation and dark matter, analyzing how specific inflaton candidates can produce observable signals consistent with CMB, LHC, and XENON1T data within the MSSM framework.

Contribution

It introduces two inflaton candidates within the MSSM that can simultaneously explain inflation, dark matter relic density, and collider constraints, providing testable predictions.

Findings

Inflaton decay can excite SM particles and thermalize the LSP.

Parameter space regions yield correct CMB anisotropy and relic density.

Predicted dark matter interactions are within XENON1T sensitivity.

Abstract

The primordial inflation dilutes all matter except the quantum fluctuations which we see in the cosmic microwave background (CMB) radiation. Therefore the last phases of inflation must be embedded within a beyond the Standard Model (SM) sector where the inflaton can directly excite the SM quarks and leptons. In this paper we consider two inflaton candidates LLe and udd whose decay can naturally excite all the relevant degrees of freedom besides thermalizing the lightest supersymmetric particle (LSP) during and after reheating. In particular, we present the regions of the parameter space which can yield successful inflation with the right temperature anisotropy in the CMB, the observed relic density for the neutralino LSP, and the recent Higgs mass constraints from LHC within the MSSM with non-universal Higgs masses -- referred to as the NUHM2 model. We found that in most scenarios, the LSP seems strongly mass degenerated with the next to lightest LSP (NLSP) and the branching ratio B_s -> mu^+ mu^- very close to the present bound, thus leading to falsifiable predictions. Also the dark matter interactions with XENON nuclei would fall within the projected range for the XENON1T experiment. In the case of a positive signal of low scale supersymmetry at the LHC, one would be able to potentially pin down the inflaton mass by using the associated values for the mass of the stau, the stop and the neutralino.