Soft-Collinear Factorization and Sudakov Resummation of Heavy Meson Decay Amplitudes with Effective Field Theories

TL;DR

This paper introduces Soft-Collinear Effective Theory to analyze B meson decay amplitudes, demonstrating factorization theorems and calculating form factors with renormalization-group improved perturbation theory.

Contribution

It provides a framework for proving factorization theorems in B decays and computes decay amplitudes and form factors using effective field theory techniques.

Findings

Factorization theorems are valid for certain B decays.

Calculated decay amplitudes for inclusive and exclusive B decays.

Form factors are dominated by non-factorizable mechanisms.

Abstract

In this thesis we present an introduction to Soft-Collinear Effective Theory, which can be used to prove (or disprove) factorization theorems to all orders in the strong coupling constant for some B decays into light and energetic particles. Specifically, the factorizable amplitudes for inclusive B->X_u l nu and exclusive B->gamma l nu are calculated in renormalization-group improved perturbation theory to first non-trivial order. Form factors encoding the exclusive decay amplitudes for B->P l nu and B->V l nu (P=light pseudoscalar meson, V=light vector meson) are studied and proved to be dominated by the non-factorizable Feynman mechanism.