Determination of heavy-meson wave functions from B decays

TL;DR

This paper extracts heavy-meson wave functions from B decay data using perturbative QCD, organizing logarithmic corrections for reliable amplitude evaluation and emphasizing the importance of transverse momentum dependence.

Contribution

It provides a novel determination of B, D, and D* meson wave functions from experimental data within a perturbative QCD framework, highlighting their universality and role in decay predictions.

Findings

Heavy-meson wave functions are extracted from CLEO data.

Wave functions depend significantly on intrinsic transverse momenta.

Results enable predictions for other decay modes.

Abstract

We extract the B, D, and D* meson wave functions from the CLEO data of the decays B -> K*\gamma and B -> D^(*)\pi in the perturbative QCD framework. In this formalism, various logarithmic corrections are organized to give the Wilson evolution from the W boson mass down to the characteristic scale of a decay process, which is of order of the b quark mass, and the Sudakov evolution from the characteristic scale to a lower factorization scale of order Lambda_{QCD}. With large logarithms organized, the b quark decay amplitudes are evaluated reliably in perturbation theory. Below the factorization scale, QCD dynamics is regarded as being nonperturbative, and absorbed into meson wave functions. Because of their universality, the heavy-meson wave functions determined in this work, can be employed to make predictions of other decay modes. We also observe that the dependence of heavy meson wave functions on intrinsic parton transverse momenta plays an important role in the explanation of data.