Decay Constants and Semileptonic Form Factors of Pseudoscalar Mesons

TL;DR

This paper uses a relativistic quark model to unify the description of leptonic and semileptonic decays of pseudoscalar mesons, achieving good agreement with experimental data and heavy-quark symmetry predictions.

Contribution

It introduces a relativistic constituent quark model that successfully describes decay constants and form factors across multiple mesons, aligning with experimental and theoretical expectations.

Findings

Accurately reproduces leptonic decay constants.

Matches experimental semileptonic form factors.

Reproduces heavy-quark symmetry scaling behaviors.

Abstract

A relativistic constituent quark model is adopted to give an unified description of the leptonic and semileptonic decays of pseudoscalar mesons (\pi, K, D, D_s, B, B_s). The calculated leptonic decay constants and form factors are found to be in good agreement with available experimental data and the results of other approaches. Eventually, the model is found to reproduce the scaling behaviours of spin-flavor symmetry in the heavy-quark limit.