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arXiv · hep-ph/0612009

Determination of fragmentation functions and their uncertainties from e+ + e- -> h + X data

M. Hirai·S. Kumano·T. -H. Nagai·K. Sudoh
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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 alpha_s. 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 Q^2 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 Q^2.

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M. Hirai, S. Kumano, T. -H. Nagai, K. Sudoh. 2006-12-01. Determination of fragmentation functions and their uncertainties from e+ + e- -> h + X data. https://doi.org/10.1063/1.2750887

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