Testing SUSY

TL;DR

This paper evaluates the naturalness of supersymmetry in the CMSSM by applying a fine-tuning measure, considering experimental limits and dark matter constraints, and identifies key measurements at the LHC for testing SUSY.

Contribution

It applies a two-loop order fine-tuning measure to the CMSSM, incorporating current experimental and dark matter constraints, to assess SUSY's viability and guide future searches.

Findings

Minimal fine tuning (1:13) corresponds to a Higgs mass of 114±2 GeV.

Fine tuning increases rapidly with heavier Higgs masses.

Current experimental limits significantly constrain the CMSSM parameter space.

Abstract

If SUSY provides a solution to the hierarchy problem then supersymmetric states should not be too heavy. This requirement is quantified by a fine tuning measure that provides a quantitative test of SUSY as a solution to the hierarchy problem. The measure is useful in correlating the impact of the various experimental measurements relevant to the search for supersymmetry and also in identifying the most sensitive measurements for testing SUSY. In this paper we apply the measure to the CMSSM, computing it to two-loop order and taking account of current experimental limits and the constraint on dark matter abundance. Using this we determine the present limits on the CMSSM parameter space and identify the measurements at the LHC that are most significant in covering the remaining parameter space. Without imposing the LEP Higgs mass bound we show that the smallest fine tuning (1:13) consistent with a relic density within the WMAP bound corresponds to a Higgs mass of 114$\pm$2 GeV. Fine tuning rises rapidly for heavier Higgs.