Charmless Two-body $B(B_s)\to VP$ decays In Soft-Collinear-Effective-Theory

TL;DR

This paper analyzes charmless two-body B and Bs decays into vector and pseudoscalar mesons using SCET, incorporating power corrections and fitting experimental data to predict decay rates and CP asymmetries, and comparing with other approaches.

Contribution

It provides a detailed SCET-based analysis of B to VP decays, including power corrections and multiple solutions for non-perturbative inputs, and compares results with QCD factorization and pQCD methods.

Findings

Two solution sets for non-perturbative inputs fit experimental data.

Chirally enhanced penguins significantly affect charming penguins.

Predictions for B_s to VP decay branching ratios and CP asymmetries.

Abstract

We provide the analysis of charmless two-body $B\to VP$ decays under the framework of the soft-collinear-effective-theory (SCET), where $V(P)$ denotes a light vector (pseudoscalar) meson. Besides the leading power contributions, some power corrections (chiraly enhanced penguins) are also taken into account. Using the current available $B\to PP$ and $B\to VP$ experimental data on branching fractions and CP asymmetry variables, we find two kinds of solutions in $\chi^2$ fit for the 16 non-perturbative inputs which are essential in the 87 $B\to PP$ and $B\to VP$ decay channels. Chiraly enhanced penguins can change several charming penguins sizably, since they share the same topology. However, most of the other non-perturbative inputs and predictions on branching ratios and CP asymmetries are not changed too much. With the two sets of inputs, we predict the branching fractions and CP asymmetries of other modes especially $B_s\to VP$ decays. The agreements and differences with results in QCD factorization and perturbative QCD approach are analyzed. We also study the time-dependent CP asymmetries in channels with CP eigenstates in the final states and some other channels such as $\bar B^0/B^0\to\pi^\pm\rho^\mp$ and $\bar B_s^0/B_s^0\to K^\pm K^{*\mp}$. In the perturbative QCD approach, the $(S-P)(S+P)$ penguins in annihilation diagrams play an important role. Although they have the same topology with charming penguins in SCET, there are many differences between the two objects in weak phases, magnitudes, strong phases and factorization properties.