Semileptonic Decays of Pseudoscalar Mesons: A New Approach

TL;DR

This paper introduces a novel approach to model semileptonic decays of pseudoscalar mesons by approximating the hadronic vertex with an effective coupling, simplifying the connection between quark-level processes and meson decays.

Contribution

It proposes a new method using an effective gamma-5 coupling to relate quark-level decays to hadronic processes, addressing QCD complexities.

Findings

Applied model to pi, K, D, and B meson decays

Simplified the calculation of hadronic decay processes

Provided a new framework for semileptonic decay analysis

Abstract

Because quarks in hadronic states are subjected to strong QCD forces, it is not straight-forward to apply calculation obtained at the quark level to physical processes involving hadrons. In this paper we present a new approach to treat the semileptonic decays of pseudoscalar mesons. At the quark level, the process is straightforward. However, when we fold the quark-level process to the meson decay process, the complication from QCD effects come in. We make the fundamental assumption that the vertex of type M-q-qbar can be approximated by an effective constant gamma-5 coupling. With this assumption, the hadronic process can then be related to the quark-level process. The model is applied to the semileptonic decays of pi, K, D and B mesons.