Global Analysis of hadronic two-body B decays in the perturbative QCD approach

TL;DR

This paper develops an automated method to analyze two-body B meson decays within the perturbative QCD framework, fitting experimental data to extract meson distribution amplitudes and fundamental parameters.

Contribution

It introduces an automatic computation program for B decay amplitudes and performs a global analysis to determine light meson LCDAs and the B_s meson shape parameter.

Findings

Fitted Gegenbauer moments agree with QCD sum rule predictions.

Determined the B_s meson distribution amplitude shape parameter.

Extracted the weak phase () consistent with PDG values.

Abstract

Based on the flavor structure of four-quark effective operators, we develop an automatic computation program to calculate hadronic two-body $B$ meson decay amplitudes, and apply it to their global analysis in the perturbative QCD (PQCD) approach. Fitting the PQCD factorization formulas for $B\to PP,VP$ decays at leading order in the strong coupling $\alpha_s$ to measured branching ratios and direct CP asymmetries, we determine the Gegenbauer moments in light meson light-cone distribution amplitudes (LCDAs). It is found that most of the fitted Gegenbauer moments of the twist-2 and twist-3 LCDAs for the pseudoscalar meson $P$ ($P=\pi$, $K$) and vector meson $V$ ($V=\rho$, $K^*$) agree with those derived in QCD sum rules. The shape parameter for the $B_s$ meson distribution amplitude and the weak phase $\phi_3(\gamma)=(75.1\pm2.9)^\circ$ consistent with the value in Particle Data Group are also obtained. It is straightforward to extend our analysis to higher orders and higher powers in the PQCD approach, and to the global determination of LCDAs for other hadrons.