Supersymmetric Custodial Triplets

TL;DR

This paper explores a supersymmetric extension of the Georgi-Machacek model, incorporating triplet superfields with custodial symmetry, and analyzes its implications for Higgs couplings and compatibility with LHC data.

Contribution

It introduces a supersymmetric model with triplet fields maintaining custodial symmetry, extending the minimal supersymmetric standard model and analyzing its phenomenological viability.

Findings

Higgs couplings align with LHC data across parameter space

Scalar sector classified into degenerate SU(2)_V multiplets

Custodial symmetry breaking suggests low-scale SUSY breaking

Abstract

We analyze the extension of the Minimal Supersymmetric Standard Model which includes extra Y=(0,\pm 1) supersymmetric triplets with a global SU(2)_L \otimes SU(2)_R symmetry spontaneousy broken to the custodial SU(2)_V by the vacuum expectation value of the neutral scalar components of doublets and triplets. The model is the supersymmetrization of the non-supersymmetric model introduced long ago by Georgi and Machacek where the \rho-parameter is kept to unity at the tree-level by the custodial symmetry. Accordingly the scalar sector is classified into degenerate SU(2)_V multiplets: singlets, triplets (including the one containing the Godstone bosons) and fiveplets. The singly and doubly charged chiral superfields play a key role in the unitarization of the theory. The couplings of the Standard Model-like Higgs to vector bosons (including \gamma\gamma) and fermions, and the corresponding Higgs signal strengths, are in agreement with LHC experimental data for a large region of the parameter space. Breaking of custodial invariance by radiative corrections suggests a low-scale mechanism of supersymmetry breaking.