Cosmology in a supersymmetric model with gauged B - L symmetry

Abstract

We consider salient cosmological features of a supersymmetric model which is left-right symmetric and therefore possessing gauged B-L symmetry. The requirement of breaking parity and also obtaining charge preserving vacua introduces some unique features to this model (MSLRM), resulting in a preference for nonthermal leptogenesis. Assuming that the model preserves TeV scale supersymmetry, we show that the vacuum structure generically possesses domain walls, which can serve two important purposes. They can signal a secondary inflation required to remove unwanted relics such as gravitino and moduli and also generate lepton asymmetry by a mechanism similar to electroweak baryogenesis. The requirement of disappearance of domain walls imposes constraints on the soft parameters of the theory, testable at the TeV scale. We also propose an alternative model with spontaneous parity violation (MSLRP). Incorporating the same cosmological considerations in this case entails constraints on a different set of soft parameters.