Implications of a 125 GeV Higgs for the MSSM and Low-Scale SUSY Breaking

TL;DR

A 125 GeV Higgs boson significantly constrains the MSSM and low-scale SUSY-breaking models, requiring heavy stops or maximal mixing, and imposes strong restrictions on SUSY mediation mechanisms.

Contribution

This paper analyzes the implications of a 125 GeV Higgs for the MSSM and low-scale SUSY-breaking, highlighting the severe constraints on model parameters and SUSY mediation.

Findings

Heavy stops (>~10 TeV) or near-maximal stop mixing are required.

In gauge mediation, gauginos may need to be superheavy or NLSP long-lived.

Stops tend to be tachyonic at high scales under these conditions.

Abstract

Recently, the ATLAS and CMS collaborations have announced exciting hints for a Standard Model-like Higgs boson at a mass of approximately 125 GeV. In this paper, we explore the potential consequences for the MSSM and low scale SUSY-breaking. As is well-known, a 125 GeV Higgs implies either extremely heavy stops (>~ 10 TeV), or near-maximal stop mixing. We review and quantify these statements, and investigate the implications for models of low-scale SUSY breaking such as gauge mediation where the A-terms are small at the messenger scale. For such models, we find that either a gaugino must be superheavy or the NLSP is long-lived. Furthermore, stops will be tachyonic at high scales. These are very strong restrictions on the mediation of supersymmetry breaking in the MSSM, and suggest that if the Higgs truly is at 125 GeV, viable models of gauge-mediated supersymmetry breaking are reduced to small corners of parameter space or must incorporate new Higgs-sector physics.