ar X iv : h ep - p h / 06 12 00 9 v 1 1 D ec 2 00 6 Determination of fragmentation functions and their uncertainties from e + + e − → h + X data
نویسنده
چکیده
Abstract. Fragmentation functions are determined for pions, kaons, and nucleons by a global analysis of charged-hadron production data in electron-positron annihilation. The optimum functions are obtained in both leading order (LO) and next-to-leading order (NLO) of αs. It is important that uncertainties of the fragmentation functions are estimated in this work by the Hessian method. We found that the uncertainties are large at small Q2 and that they are generally reduced in the NLO in comparison with the LO ones. We supply a code for calculating the fragmentation functions and their uncertainties for the pions, kaons, and nucleons at given z and Q2.
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