Precise pion and kaon multiplicities at BELLE

Fragmentation functions (FFs) describe the formation of final state particles from a partonic initial state. Precise knowledge of these functions, especially spin-average FFs, 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 Quantum Chromodynamics first principles and have to be extracted from experimental data. The Belle experiment at KEK, Japan, provides a large data sample for high precision measurements of unpolarized and polarized fragmentation functions. Here, final extraction of the spin-independent FFs for identified pions and kaons will be presented.