Bounds on R-parity Violating Couplings at the Weak Scale and at the GUT Scale

TL;DR

This paper updates experimental bounds on R-parity violating couplings, analyzes their values at the GUT scale through renormalization, and derives scale-dependent bounds that are more restrictive at high energies, considering fermion mixing effects.

Contribution

It provides the first comprehensive analysis of R-parity violating couplings at the GUT scale, including renormalization effects and bounds considering fermion mixing and perturbativity constraints.

Findings

R-parity violating couplings are more tightly bounded at the GUT scale.

Fermion mixing induces stronger bounds due to new operators.

Perturbativity imposes additional constraints on weak scale couplings.

Abstract

We present an update of the most stringent experimental bounds on the trilinear R-parity violating couplings. We then analyse bounds on the R-parity violating couplings at the unification scale by renormalising the weak scale bounds. We derive unification scale upper bounds upon the couplings which are broadly independent of the fermion mass texture assumed. The R-parity violating couplings are factors of two to five more severely bounded at the unification scale than at the electroweak scale. In the presence of quark mixing, a few of the bounds are orders of magnitude stronger than their weak scale counterparts due to new R-parity violating operators being induced in the renormalisation between high and low scales. These induced bounds are fermion mass texture dependent. New bounds upon the weak scale couplings are obtained by the requirement of perturbativity between the weak and unification scales. A comprehensive set of the latest limits is included.