Baryon-Number-Violating Nucleon and Dinucleon Decays in a Model with Large Extra Dimensions

TL;DR

This paper explores how a model with large extra dimensions suppresses baryon-number-violating nucleon and dinucleon decays, aligning theoretical predictions with experimental constraints through effective field theory analysis.

Contribution

It provides a detailed analysis of nucleon decay rates in a higher-dimensional model, demonstrating suppression mechanisms for rare decay processes.

Findings

Decay rates for nucleon and dinucleon processes are strongly suppressed.

The model is consistent with current experimental limits on baryon-number violation.

Effective field theory analysis supports the suppression of rare decay modes.

Abstract

It is known that limits on baryon-violating nucleon decays do not, in general, imply corresponding suppression of $n - \bar n$ transitions. In the context of a model with fermions propagating in higher dimensions, we investigate a related question, namely the implications of limits on $\Delta L=-1$ proton and bound neutron decays mediated by four-fermion operators for rates of nucleon decays mediated by $k$-fermion operators with $k =6$ and $k=8$. These include a variety of nucleon and dinucleon decays to dilepton and trilepton final states with $\Delta L=-3, \ -2, \ 1$, and $2$. We carry out a low-energy effective field theory analysis of relevant operators for these decays and show that, in this extra-dimensional model, the rates for these decays are strongly suppressed and hence are in accord with experimental limits.