Neutrino masses and sparticle spectra from stochastic superspace

TL;DR

This paper improves calculations of sparticle spectra from stochastic superspace, explores neutrino mass generation mechanisms, and discusses experimental implications for the minimal supersymmetric model.

Contribution

It provides two-loop accuracy spectra calculations, examines R-parity violation and seesaw extensions, and assesses their phenomenological viability.

Findings

Global decrease in sparticle masses with improved calculations

Stop decay channels accessible at the LHC for model falsification

Neutrino masses via R-parity violation are viable without dark matter candidate

Abstract

Based on the stochastic superspace mechanism for softly breaking supersymmetry, we present improved sparticle spectra computations for the minimal model and examine extensions through R-parity violation and the type-I seesaw mechanism that incorporate non-zero neutrino masses for more realistic models. Performing the calculations to two-loop accuracy, we observe a global decrease in predicted sparticle masses. However this does not affect the generic features of the minimal model outlined in our earlier work, including the characteristic light stop mass. We find stop decay channels accessible at the LHC which can be used in combination with our predicted range for the stop mixing angle to falsify the minimal model with stochastic supersymmetry. We then introduce neutrino masses and mixings consistent with experiment by including purely trilinear R-parity violating superpotential terms, resulting in a viable stochastic superspace model absent a dark matter candidate. An alternative method for generating neutrino masses, namely the type-I seesaw mechanism, is found only to be viable when the neutrino Yukawa coupling is small relative to the top Yukawa and the cut-off scale is large.