Simultaneous B and L Violation: New Signatures from RPV-SUSY

TL;DR

This paper introduces a new class of RPV supersymmetry models that violate baryon and lepton numbers simultaneously without causing rapid nucleon decay, leading to unique collider signatures and relaxed nucleon decay constraints.

Contribution

The paper proposes BLRPV models with an approximate flavor symmetry, predicting novel nucleon decay modes and distinctive collider phenomenology with mixed B and L violation signatures.

Findings

Nucleon decay modes include N → K e μ ν and n → e μ ν.

Collider signatures feature high jet multiplicity and multiple flavor leptons.

Nucleon decay bounds on RPV couplings are relatively mild.

Abstract

Studies of R-parity violating (RPV) supersymmetry typically assume that nucleon stability is protected by approximate baryon number (B) or lepton number (L) conservation. We present a new class of RPV models that violate B and L simultaneously (BLRPV), without inducing rapid nucleon decay. These models feature an approximate $Z_2^e \times Z_2^\mu \times Z_2^\tau$ flavor symmetry, which forbids 2-body nucleon decay and ensures that flavor antisymmetric $L L E^c$ couplings are the only non-negligible L-violating operators. Nucleons are predicted to decay through $N \rightarrow K e \mu \nu$ and $n \rightarrow e \mu \nu$; the resulting bounds on RPV couplings are rather mild. Novel collider phenomenology arises because the superpartners can decay through both L-violating and B-violating couplings. This can lead to, for example, final states with high jet multiplicity and multiple leptons of different flavor, or a spectrum in which depending on the superpartner, either B or L violating decays dominate. BLRPV can also provide a natural setting for displaced $\tilde{\nu} \rightarrow \mu e$ decays, which evade many existing collider searches for RPV supersymmetry.