Meson distribution amplitudes in holographic models

TL;DR

This paper compares light and heavy meson wave functions in hard-wall and soft-wall holographic models using AdS/CFT, highlighting differences with quark mass dependence and implications for decay constants and distribution amplitudes.

Contribution

It introduces quark mass dependence into holographic meson wave functions and compares the resulting distribution amplitudes and decay constants across two models.

Findings

Distribution amplitudes are similar for massless constituents in both models.

Introducing quark mass dependence reveals clear differences in distribution amplitudes.

Decay constants depend differently on the dilaton scale parameter, aligning with heavy quark effective theory predictions.

Abstract

We study the wave functions of light and heavy mesons in both hard-wall (HW) and soft-wall (SW) holographic models which use AdS/CFT correspondence. In the case of massless constituents, the asymptotic behaviors of the electromagnetic form factor, the distribution amplitudes, and the decay constants for the two models are the same, if the relation between the dilaton scale parameter and the size of meson is an inverse proportion. On the other hand, by introducing a quark mass dependence in the wave function, the differences of the distribution amplitudes between the two models are obvious. In addition, for the SW model, the dependences of the decay constants of meson on the dilaton scale parameter $\kappa$ differ; especially f_{Qq}\sim \kappa^3/m_Q^2 is consistent with the prediction of the heavy quark effective theory if \kappa\sim m_Q^{1/2}. Thus the parameters of the two models are fit by the decay constants of the distinct mesons; the distribution amplitudes and the \xi-moments are calculated and compared.