Charm Hadrons from Fragmentation and B decays in e+e- Annihilation at $\sqrt{s}=$10.6 GeV

TL;DR

This paper analyzes charm quark fragmentation into various charmed hadrons at 10.6 GeV using Belle data, providing measurements of fragmentation functions, production angles, and yields in B decays.

Contribution

It offers new measurements of charm fragmentation functions, production angles, and yields at 10.6 GeV, improving understanding of low-energy QCD processes and aiding Monte Carlo simulations.

Findings

Fragmentation functions for D, D_s, and Lambda_c measured.

Average number of charmed hadrons per B decay determined.

Production angle distributions characterized.

Abstract

We present an analysis of charm quark fragmentation at 10.6 GeV, based on a data sample of 103 fb collected by the Belle detector at the KEKB accelerator. We consider fragmentation into the main charmed hadron ground states, namely \DZ, \DP, \Ds and \LC, as well as the excited states \DSZ and \DSP. The fragmentation functions are important to measure as they describe processes at a low energy scale, where calculations in perturbation theory lead to large uncertainties. Fragmentation functions can also be used as input distributions for Monte Carlo generators. Additionally, we determine the average number of these charmed hadrons produced per B decay at the \Ys resonance and measure the distribution of their production angle in \epem annihilation events and in B decays.