Fragmentation Functions ∗
نویسنده
چکیده
We estimate the power corrections (infrared renormalon contributions) to the coefficient functions for the transverse, longitudinal and asymmetric fragmentation functions in e + e − annihilation, using a method based on the analysis of one-loop Feynman graphs containing a massive gluon. The leading corrections have the expected 1/Q 2 behaviour, but the gluonic coefficients of the longitudinal and transverse contributions separately have strong singularities at small x, which cancel in their sum. This leads to 1/Q corrections to the longitudinal and transverse parts of the annihilation cross section, which cancel in the total cross section.
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