Exploring flavour space of an economical SU(5) GUT in future proton decay measurements

TL;DR

This paper investigates how future proton decay experiments can probe the flavor structure of an economical SU(5) GUT model, focusing on the potential to test unobservable parameters through multi-channel decay analysis.

Contribution

It introduces a minimal SU(5) GUT model with a single 24-plet extension and explores how future proton decay data can test flavor parameters beyond current measurement capabilities.

Findings

Hierarchical fermion masses in the 24-plet are necessary for gauge unification.

Future proton decay experiments can test otherwise inaccessible flavor parameters.

Multi-channel analysis enhances the ability to probe the model's flavor space.

Abstract

We discuss the potential of future proton decay experiments on the exploration of the flavour space of grand unification. We focus on an economical $SU(5)$ grand unified model (GUT) with the fermion sector extended by including only one copy of 24-plet. Neutrino masses are generated via type-(I+III) seesaw mechanism with the lightest neutrino massless. Gauge unification requires masses of fermions in the 24-plet to be hierarchical, in particular, the electroweak singlet and triplet heavy leptons to be around the canonical seesaw scale and TeV scale, respectively. We address how extra parameters in the flavour space which cannot be touched in flavour measurements can be tested by a multi-channel analysis in future proton decay measurements.