A Heavy Higgs and a Light Sneutrino NLSP in the MSSM with Enhanced SU(2) D-terms

TL;DR

This paper explores how enhanced SU(2) D-terms in the MSSM can naturally increase the Higgs boson mass, influence the superpartner spectrum, and impact collider and cosmological phenomenology.

Contribution

It demonstrates that enhanced SU(2) D-terms not only raise the Higgs mass but also modify the spectrum of non-standard Higgs bosons and sleptons, providing a natural solution to the Higgs mass challenge.

Findings

Enhanced D-terms increase Higgs mass beyond LEP bounds.

Modified spectrum includes light sneutrino NLSP and inert-like Higgs doublet.

Models have distinctive collider signatures and cosmological implications.

Abstract

The Minimal Supersymmetric extension of the Standard Model provides a solution to the hierarchy problem and leads to the presence of a light Higgs. A Higgs boson with mass above the present experimental bound may only be obtained for relatively heavy third generation squarks, requiring a precise, somewhat unnatural balance between different contributions to the effective Higgs mass parameter. It was recently noticed that somewhat heavier Higgs bosons, which are naturally beyond the LEP bound, may be obtained by enhanced weak SU(2) D-terms. Such contributions appear in models with an enhanced electroweak gauge symmetry, provided the supersymmetry breaking masses associated with the scalars responsible for the breakdown of the enhanced gauge symmetry group to the Standard Model one, are larger than the enhanced symmetry breaking scale. In this article we emphasize that the enhanced SU(2) D-terms will not only raise the Higgs boson mass but also affect the spectrum of the non-standard Higgs bosons, sleptons and squarks, which therefore provide a natural contribution to the T parameter, compensating for the negative one coming from the heavy Higgs boson. The sleptons and non-standard Higgs bosons of these models, in particular, may act in a way similar to the so-called inert Higgs doublet. The phenomenological properties of these models are emphasized and possible cosmological implications as well as collider signatures are described.