Explicit Soft Supersymmetry Breaking in the Heterotic M-Theory $B-L$ MSSM

TL;DR

This paper explores explicit soft supersymmetry breaking in heterotic M-theory's $B-L$ MSSM, analyzing gaugino condensation, moduli stabilization, and resulting low-energy phenomenology compatible with LHC energy scales.

Contribution

It provides a detailed computation of gaugino condensation scales, moduli-dependent soft terms, and identifies regions in K"ahler moduli space that yield realistic low-energy physics.

Findings

Identification of a line bundle with low enough condensation scale for LHC compatibility

Explicit calculation of moduli-dependent soft supersymmetry breaking terms

Demonstration that many initial conditions lead to phenomenologically viable models

Abstract

The strongly coupled heterotic M-theory vacuum for both the observable and hidden sectors of the $B-L$ MSSM theory is reviewed, including a discussion of the "bundle" constraints that both the observable sector $SU(4)$ vector bundle and the a hidden sector bundle induced from a line bundle must satisfy. Gaugino condensation is then introduced within this context, and the hidden sector bundles that exhibit gaugino condensation are presented. The condensation scale is computed, singling out one line bundle whose associated condensation scale is low enough to be compatible with the energy scales available at the LHC. The corresponding region of K\"ahler moduli space where all bundle constraints are satisfied is presented. The generic form of the moduli dependent $F$-terms due to a gaugino superpotential - which spontaneously break $N=1$ supersymmetry in this sector - is presented and then given explicitly for the unique line bundle associated with the low condensation scale. The moduli dependent coefficients for each of the gaugino and scalar field soft supersymmetry breaking terms are computed leading to a low-energy effective Lagrangian for the observable sector matter fields. We then show that at a large number of points in K\"ahler moduli space that satisfy all "bundle" constraints, these coefficients are initial conditions for the renormalization group equations which, at low energy, lead to completely realistic physics satisfying all phenomenological constraints. Finally, we show that a substantial number of these initial points also satisfy a final constraint arising from the quadratic Higgs-Higgs conjugate soft supersymmetry breaking term.