Study of the Growth of Entropy Modes in MSSM Flat Directions Decay: Constraints on the Parameter Space

TL;DR

This paper investigates how resonant decay of MSSM moduli fields can amplify entropy perturbations, influencing the curvature power spectrum and providing constraints on particle physics parameters without collider data.

Contribution

It introduces a method to constrain MSSM parameters by analyzing entropy mode growth during moduli decay affecting cosmological perturbations.

Findings

Resonant decay can exponentially amplify entropy perturbations.

Constraints on MSSM parameters derived from COBE normalization.

Method applicable to other beyond Standard Model theories.

Abstract

We study how the resonant decay of moduli fields arising in the Minimal Supersymmetric Standard Model (MSSM) could affect large scale curvature perturbations in the early universe. It has been known for some time that the presence of entropy perturbations in a multi-component system can act as seeds for the curvature perturbations on all scales. These entropy perturbations could be amplified exponentially if one of the moduli decays via stochastic resonance, affecting the curvature power spectrum in the process. By imposing the COBE normalization on this power spectrum, one could put constraints on the masses and couplings of the underlying particle physics model without having to rely on collider experiments. We discuss in detail the case of the MSSM but this method could be applied to other theories beyond the Standard Model.