Determination of the b-quark leading shape function parameters in the shape function scheme using the Belle B->X_s gamma photon energy spectrum

TL;DR

This paper extracts the b-quark shape function parameters from Belle B->X_s gamma data using three different models, enhancing understanding of the quark's behavior in B-meson decays.

Contribution

It introduces a method to determine shape function parameters in the shape function scheme using experimental photon energy spectra with multiple model assumptions.

Findings

Determined b-quark shape function parameters m_b(SF) and μ_π^2(SF).

Compared exponential, gaussian, and hyperbolic models for the shape function.

Provided insights into the model dependence of the parameters.

Abstract

We determine the b-quark shape function parameters in the shape function scheme, m_b(SF) and \mu_\pi^2(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 hyperbolic.