SCET sum rules for B->P and B->V transition form factors

TL;DR

This paper derives sum rules for heavy-to-light B meson transition form factors using SCET, analyzing factorizable and non-factorizable contributions at leading power and first order in alpha_s, with focus on uncertainties and form factor ratios.

Contribution

It introduces SCET-based sum rules for B->P and B->V transition form factors, including systematic uncertainty analysis and form factor ratio discussions.

Findings

Sum rules derived for B->P and B->V form factors.

Identification of uncertainties affecting form factor calculations.

Cancellation of some uncertainties in specific form factor ratios.

Abstract

We investigate sum rules for heavy-to-light transition form factors at large recoil derived from correlation functions with interpolating currents for light pseudoscalar or vector fields in soft-collinear effective theory (SCET). We consider both, factorizable and non-factorizable contributions at leading power in the Lambda/m_b expansion and to first order in the strong coupling constant alpha_s, neglecting contributions from 3-particle distribution amplitudes in the B-meson. We pay particular attention to various sources of parametric and systematic uncertainties. We also discuss certain form factor ratios where part of the hadronic uncertainties related to the B-meson distribution amplitude and to logarithmically enhanced alpha_s corrections cancel.