The minimal SUSY B − L model: from the unification scale to the LHC

Burt A Ovrut,Sogee Spinner,Austin Purves

doi:10.1007/jhep06(2015)182

Abstract

This paper introduces a random statistical scan over the high-energy initial parameter space of the minimal SUSY B − L model — denoted as the B − L MSSM. Each initial set of points is renormalization group evolved to the electroweak scale — being subjected, sequentially, to the requirement of radiative B − L and electroweak symmetry breaking, the present experimental lower bounds on the B − L vector boson and sparticle masses, as well as the lightest neutral Higgs mass of ∼125 GeV. The subspace of initial parameters that satisfies all such constraints is presented, shown to be robust and to contain a wide range of different configurations of soft supersymmetry breaking masses. The low-energy predictions of each such “valid” point — such as the sparticle mass spectrum and, in particular, the LSP — are computed and then statistically analyzed over the full subspace of valid points. Finally, the amount of fine-tuning required is quantified and compared to the MSSM computed using an identical random scan. The B − L MSSM is shown to generically require less fine-tuninng.

Highlights

Broken [9,10,11]
This paper introduces a random statistical scan over the high-energy initial parameter space of the minimal SUSY B − L model — denoted as the B − L MSSM
For the B − L MSSM to be a realistic contender for the low-energy theory of particle physics, it is essential that its initial parameter space be explored in a generic way, and that its low-energy

Summary

Introduction

Broken [9,10,11]. These are all “non-minimal” in the sense, for example, that they require additional matter multiplets, have other ad hoc assumptions and so on. An important aspect of this high-energy point of view is that the parameters of the theory are specified near the gauge coupling unification scale, and run down to the electroweak scale using the renormalization group (RG). This allows one to explore fundamental aspects of the theory — such as B − L and electroweak symmetry breaking. For the B − L MSSM to be a realistic contender for the low-energy theory of particle physics, it is essential that its initial parameter space be explored in a generic way, and that its low-energy predictions be compared with all present experimental data This will be carried out in detail in this paper. The section finishes by describing — and implementing — the well-known bounds from flavor changing neutral currents and CP violation

Objectives

Results

Conclusion