Chiral perturbation theory for baryon-number-violating nucleon decay into a vector meson

Abstract: In a recent work \cite{Liao:2025vlj} we identified generic baryon-number-violating (BNV) structures containing triple light quarks and achieved their leading-order chiral realizations involving octet pseudoscalars and baryons. Although many two-body nucleon decays into a vector meson have been experimentally searched for and stringently constrained, a consistent theoretical framework for their calculation is still lacking. In this Letter, we fill the gap by implementing chiral matching of all these triple-quark interactions onto hadronic interactions involving octet vector mesons, baryons, and pseudoscalars. This paves the way for a consistent and comprehensive study of all relevant BNV processes. As an illustration of application, we show how degeneracy in the parameter space of Wilson coefficients can be broken by synthesizing experimental constraints on nucleon decays into a vector or pseudoscalar meson when relevant hadronic low energy constants can be reasonably determined.