Vol. 7 (2014) Acta Physica Polonica B Proceedings Supplement No 3 THE ROLE OF HADRONIZATION PROCESSES IN DETERMINATION OF FRAGMENTATION FUNCTIONS * M. Soleymaninia a,b , Ali N. Khorramian c,b S. Mohammad Moosavi Nejad d,b , F. Arbabifar e,b a Faculty of Engineering, University of Science and Culture, Tehran, Iran b School of Particles and Accelerators Institute for Research in Fundamental Sciences (IPM) P.O. Box 19395-5531, Tehran, Iran c Physics Department, Semnan University, Semnan, Iran d Faculty of Physics, Yazd University, P.O. Box 89195-741, Yazd, Iran e Islamic Azad University, North Tehran Beanch, Tehran, Iran (Received May 26, 2014) We present the results of a global fit to data from different hadroniza- tion processes such as single-inclusive electron–positron annihilation and semi-inclusive deep inelastic scattering to calculate pion and kaon frag- mentation functions. We perform an improvement to the pion and kaon fragmentation functions at next-to-leading order (NLO), by including re- cent single-inclusive electron–positron annihilation data from BaBar and Belle at Q = 10.54 GeV and Q = 10.52 GeV, respectively. Our main purpose is to show how much imposing of these new data in our analysis improves the fragmentation functions of pion and kaon at NLO. DOI:10.5506/APhysPolBSupp.7.573 PACS numbers: 13.66.Bc, 13.85.Ni, 13.87.Fh 1. Introduction Fragmentation functions (FFs) are the key quantities in calculation of hadron production cross sections, investigating properties of quarks in heavy ion collisions and spin physics. In order to study the properties of the top quark at the LHC, one of the proposed channels is to consider the energy spectrum of outgoing mesons from top quark decays, in which having the required information about the FFs is crucial. ∗ Presented by M. Soleymaninia at “Excited QCD 2014”, Bjelašnica Mountain, Sara- jevo, Bosnia and Herzegovina, February 2–8, 2014. (573)