Fragmentation Functions at Belle

TL;DR

This paper discusses the extraction of fragmentation functions from Belle experiment data, which are crucial for understanding particle formation and are not currently calculable from first principles in QCD.

Contribution

It presents new high-precision measurements of fragmentation functions, including both unpolarized and spin-dependent types, from Belle's e+e- annihilation data.

Findings

First-time extraction of spin-dependent fragmentation functions.

More precise measurements of unpolarized fragmentation functions.

Enhanced understanding of particle formation processes.

Abstract

Fragmentation functions (FFs) describe the formation of final state particles from a partonic initial state. Precise knowledge of these functions is a key ingredient in accessing quantities such as the nucleon spin structure in semi-inclusive deep-inelastic scattering and proton proton collisions. However, fragmentation functions can currently not be determined from first principles Quantum Chromodynamics and have to be extracted from experimental data. The Belle experiment at KEK, Japan, provides a large data sample for high precision measurements on e^{+}e^{-} annihilations allowing for first-time or more precise extractions of fragmentation functions. Analyses for extractions of spin-independent (unpolarized FFs) as well as spin-dependent fragmentation functions (interference FFs) at Belle are presented.