New Minimal Extension of MSSM

TL;DR

This paper introduces a minimal extension of the MSSM that promotes the $mbda$-parameter to a singlet superfield, solving the $mbda$-problem while avoiding phenomenological and cosmological issues.

Contribution

It proposes a new minimal MSSM extension with a $mbda$-promoted singlet superfield, enforced by a $\u21135$ $R$-symmetry, providing a natural solution to the $mbda$-problem.

Findings

The model naturally solves the $mbda$-problem.

It remains free from phenomenological issues.

It avoids cosmological problems associated with previous models.

Abstract

We construct a new minimal extension of the Minimal Supersymmetric Standard Model (MSSM) by promoting the $\mu$-parameter to a singlet superfield. The resulting renormalizable superpotential is enforced by a $\mathcal{Z}_5$ $R$-symmetry which is imposed on the non-renormalizable operators as well. The proposed model provides a natural solution to the $\mu$-problem and is free from phenomenological and cosmological problems.