Supersymmetry Signals of Supercritical String Cosmology at the Large Hadron Collider

TL;DR

This paper explores how supercritical string cosmology modifies supersymmetry signals at the LHC, especially in dark matter predictions, leading to distinctive final states involving Z bosons, Higgs bosons, and taus.

Contribution

It introduces a framework for analyzing mSUGRA signals within supercritical string cosmology, highlighting how a dynamic dilaton alters dark matter constraints and collider signatures.

Findings

Dilutes neutralino dark matter density by a factor of about 10.

Allows regions with excessive dark matter in standard cosmology to be viable.

Provides methods to characterize LHC final states and determine model parameters.

Abstract

We investigate the minimal supergravity (mSUGRA) signals at the LHC in the context of supercritical string cosmology (SSC). In this theory, the presence of a time dependent dilaton provides us with a smoothly evolving dark energy and modifies the dark matter allowed region of the mSUGRA model with standard cosmology. Such a dilaton dilutes the supersymmetric dark matter density (of neutralinos) by a factor O(10) and consequently the regions with too much dark matter in the standard scenario are allowed in the SSC. The final states expected at the LHC in this scenario, unlike the standard scenario, consist of Z bosons, Higgs bosons, and/or high energy taus. We show how to characterize these final states and determine the model parameters. Using these parameters, we determine the dark matter content and the neutralino-proton cross section. All these techniques can also be applied to determine model parameters in SSC models with different SUSY breaking scenarios.