Power corrections in e+ e- --> pi+ pi-, K+ K- and B --> K pi, pi pi

TL;DR

This paper investigates power corrections in specific meson decay processes and form factors at energies near the B meson mass, distinguishing between perturbative and soft contributions, and finds a dominance of soft-overlap effects consistent with the Standard Model.

Contribution

It provides a detailed separation of perturbative and soft power corrections in meson form factors and B decay amplitudes, highlighting the soft-overlap dominance at energies near m_B.

Findings

Soft power corrections are at least ten times larger than perturbative ones.

A soft-to-perturbative hierarchy of order ten is observed in QCD penguin corrections.

The fit results are consistent with the Standard Model and support the soft-overlap dominance hypothesis.

Abstract

CLEO-c measurements of the timelike form factors F_pi, F_K at \sqrt{s}=3.671 GeV provide a direct probe of power corrections (PC's) at energies near m_B. PC's in F_pi, F_K and B \to K pi, pi pi are separated into perturbative and soft parts. In F_pi, F_K the latter are \ge O(10) larger. A PC fit to the B \to K pi, pi pi data also yields a \ge O(10) soft-to-perturbative hierarchy for the QCD penguin PC's. Hence, both can be attributed to dominance of the soft-ovelap between energetic (approximately) back-to-back collinear partons, and consistency of the B\to K pi, pi pi fit with the Standard Model appears to be naturally realized. The CP asymmetries S_{K_s pi^0}, C_{K_s pi^0} are well determined, providing a clean test for new physics.