QCD sum rules on the light cone and B -> pi form factors

TL;DR

This paper discusses using light-cone QCD sum rules to accurately calculate B to pi transition form factors, crucial for determining the CKM matrix element |V_{ub}| from semileptonic B decays.

Contribution

It presents a systematic approach incorporating QCD corrections and higher twist effects within light-cone sum rules for B to pi form factors.

Findings

Provides a reliable method for calculating B -> pi form factors.

Includes systematic treatment of QCD corrections.

Addresses higher twist contributions for improved accuracy.

Abstract

The semileptonic decay B -> pi l nu is one of the most important reactions for the determination of the CKM matrix element |V_{ub}|. However, in order to extract |V_{ub}| from data one needs an accurate theoretical calculation of the hadronic matrix element describing the B to pi transition. QCD sum rules, based on operator-product expansion on the light-cone, provide a reliable approach to this aim. QCD corrections and higher twist contributions can be taken systematically into account.