Revisiting Charmless Hadronic B_{u,d} Decays in QCD Factorization

TL;DR

This paper revisits charmless hadronic B meson decays within QCD factorization, exploring power corrections like penguin annihilation and soft effects to resolve CP puzzles and rate deficits, with predictions aligning well with experimental data.

Contribution

It introduces a detailed analysis of power correction effects in QCDF to address CP and rate puzzles in B decays, comparing with pQCD and SCET approaches.

Findings

Certain decay channels require penguin annihilation for correct CP violation.

Some decays need both power corrections to match measured CP asymmetries.

QCDF predictions agree well with experimental branching fractions and CP asymmetries.

Abstract

Within the framework of QCD factorization (QCDF), we consider two different types of power correction effects in order to resolve the CP puzzles and rate deficit problems with penguin-dominated two-body decays of B mesons and color-suppressed tree-dominated $\pi^0\pi^0$ and $\rho^0\pi^0$ modes: penguin annihilation and soft corrections to the color-suppressed tree amplitude. We emphasize that the electroweak penguin solution to the $B\to K\pi$ CP puzzle via New Physics is irrelevant for solving the CP and rate puzzles related to tree-dominated decays. While some channels e.g. $K^-\pi^+,K^-\rho^0,\pi^+\pi^-,\rho^\pm\pi^\mp$ need penguin annihilation to induce the correct magnitudes and signs for their CP violation, some other decays such as $B^-\to K^-\pi^0,\pi^-\eta, K^-\eta$ and $\bar B^0\to \bar K^{*0}\eta,\pi^0\pi^0$ require the presence of both power corrections to account for the measured CP asymmetries. In general, QCDF predictions for the branching fractions and direct CP asymmetries of $\bar B\to PP,VP,VV$ decays are in good agreement with experiment. The predictions of pQCD and soft-collinear effective theory are included for comparison.