Three-generation baryon and lepton number violation at the LHC

TL;DR

This paper explores three-generation baryon and lepton number violation at the LHC, showing that flavor symmetries allow observable violations consistent with low-energy constraints, and identifies distinctive signals for such processes.

Contribution

It introduces model-independent classes of B and L violating processes that satisfy constraints and predicts unique LHC signatures based on simplified models.

Findings

Identifies flavor symmetry considerations that reconcile B and L violation with low-energy constraints.

Proposes specific LHC signals such as t μ+ e+ and t t̄ + jets for B and L violation.

Demonstrates the viability of observing baryon and lepton number violation at high energies.

Abstract

One of the most puzzling questions in particle physics concerns the status of the baryon (B) and lepton (L) quantum numbers. On the theoretical side, most new physics scenarios naturally lead to their non-conservation and some amount of violation is actually needed to explain the baryon asymmetry of the Universe. On the experimental side, low-energy constraints such as those on proton decay are so stringent that it is generally believed that no B and L violation will ever be seen in laboratories. We observe that this apparent contradiction, however, disappears when the flavor symmetries involving all three generations are taken into account. We then identify model-independent classes of B and/or L violating six-fermion-based processes that indeed simultaneously satisfy low-energy constraints and produce clearly identifiable signals at the LHC. Finally, through simplified models, we study two classes characterized by (\Delta B;\Delta L) = (\pm 1;\pm 3) and (\pm 2; 0), that lead to particularly striking signatures (t \mu^+ e^+ and \bar t \bar t + jets, respectively).