Supersymmetry, Nonthermal Dark Matter and Precision Cosmology

TL;DR

This paper explores how nonthermal dark matter production in the MSSM, influenced by high superpartner masses and moduli fields, affects cosmological observables and astrophysical signals, providing new constraints on neutralino models.

Contribution

It analyzes the impact of nonthermal dark matter on inflationary parameters and astrophysical bounds within the MSSM, incorporating effects of high superpartner masses and moduli fields.

Findings

Nonthermal dark matter can have higher self-interaction cross-sections.

Moduli fields induce a long matter-dominated phase affecting cosmological parameters.

Constraints on neutralino composition are derived from astrophysical and detection bounds.

Abstract

Within the Minimal Supersymmetric Standard Model (MSSM), LHC bounds suggest that scalar superpartner masses are far above the electroweak scale. Given a high superpartner mass, nonthermal dark matter is a viable alternative to WIMP dark matter generated via freezeout. In the presence of moduli fields nonthermal dark matter production is associated with a long matter dominated phase, modifying the spectral index and primordial tensor amplitude relative to those in a thermalized primordial universe. Nonthermal dark matter can have a higher self-interaction cross-section than its thermal counterpart, enhancing astrophysical bounds on its annihilation signals. We constrain the contributions to the neutralino mass from the bino, wino and higgsino using existing astrophysical bounds and direct detection experiments for models with nonthermal neutralino dark matter. Using these constraints we quantify the expected change to inflationary observables resulting from the nonthermal phase.