Extraction of the b-quark shape function parameters using the Belle B->X_s gamma photon energy spectrum

TL;DR

This paper determines the parameters of the b-quark shape function by analyzing the photon energy spectrum in B->X_s gamma decays using data from the Belle experiment.

Contribution

It introduces a method to extract shape function parameters using three different models based on experimental photon energy spectra.

Findings

Estimated shape function parameters for each model

Comparison of model fits to experimental data

Constraints on theoretical models of B-meson decays

Abstract

We determine the b-quark shape function parameters, Lambda^SF and lambda_1^SF using the Belle B->X_s gamma photon energy spectrum. We assume three models for the form of the shape function; Exponential, Gaussian and Roman.