Problem of Nucleon Production in the Quark Parton Model

摘要

Quark fragmentation into hadrons, esp. nucleons, is studied fitting empirical fragmentation functions to e exp + e exp - annihilation data. We find fragmentation functions deviating from counting rule predictions as well as from scaling due to the threshold in kaon and nucleon production. Using these fragmentation functions we study particle production ratios in ep and large transverse momentum hadronic reactions. In both cases we find the ratios p/ pi exp + and antip/ pi exp - to agree roughly in magnitude with the measured ratios. The model is however inconsistent with the transverse momentum behaviour of large transverse momentum proton spectra. (Atomindex citation 08:342277)