Phenomenology of a supersymmetricU(1)B−L×U(1)Rextension of the standard model with inverse seesaw mechanism

Abstract

We discuss the minimal supersymmetric $U(1{)}_{B\ensuremath{-}L}\ifmmode\times\else\texttimes\fi{}U(1{)}_{R}$ extension of the standard model. Gauge couplings unify as in the minimal supersymmetric standard model (MSSM), even if the scale of $U(1{)}_{B\ensuremath{-}L}\ifmmode\times\else\texttimes\fi{}U(1{)}_{R}$ breaking is as low as order TeV and the model can be embedded into a $SO(10)$ grand unified theory. The phenomenology of the model differs in some important aspects from the MSSM, leading potentially to rich phenomenology at the LHC. It predicts more light Higgs states and the mostly left $CP$-even Higgs having a mass that easily reaches 125 GeV, with no constraints on the supersymmetry spectrum. Right sneutrinos can be the lightest supersymmetric particle, changing all dark matter constraints on supersymmetry parameter space. The model has seven neutralinos, and squark/gluino decay chains involve more complicated cascades than in the MSSM. We also briefly discuss low-energy and accelerator constraints on the model, where the most important limits come from recent ${Z}^{\ensuremath{'}}$ searches at the LHC and upper limits on lepton flavor violation.