The Super-GUT CMSSM Revisited

TL;DR

This paper revisits minimal supersymmetric SU(5) GUT models with universal soft-breaking parameters at a high scale, analyzing constraints from proton decay, Higgs mass, and dark matter to identify viable parameter regions.

Contribution

It extends previous super-GUT CMSSM studies by incorporating proton lifetime and Higgs mass constraints, exploring a broader parameter space for compatibility with phenomenological data.

Findings

Viable parameter regions are typically in the multi-TeV range for scalar and gaugino masses.

Allowed models favor low tan beta, around 6 or less.

Parameter space depends on unknown GUT-scale phases and superpotential couplings.

Abstract

We revisit minimal supersymmetric SU(5) grand unification (GUT) models in which the soft supersymmetry-breaking parameters of the minimal supersymmetric Standard Model (MSSM) are universal at some input scale, $M_{in}$, above the supersymmetric gauge coupling unification scale, $M_{GUT}$. As in the constrained MSSM (CMSSM), we assume that the scalar masses and gaugino masses have common values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$, as do the trilinear soft supersymmetry-breaking parameters $A_0$. Going beyond previous studies of such a super-GUT CMSSM scenario, we explore the constraints imposed by the lower limit on the proton lifetime and the LHC measurement of the Higgs mass, $m_h$. We find regions of $m_0$, $m_{1/2}$, $A_0$ and the parameters of the SU(5) superpotential that are compatible with these and other phenomenological constraints such as the density of cold dark matter, which we assume to be provided by the lightest neutralino. Typically, these allowed regions appear for $m_0$ and $m_{1/2}$ in the multi-TeV region, for suitable values of the unknown SU(5) GUT-scale phases and superpotential couplings, and with the ratio of supersymmetric Higgs vacuum expectation values $\tan \beta \lesssim 6$.