Um{p-95{23 Rechp{95{09 Revised Version Gluon Fragmentation into 3 P J Quarkonium
نویسنده
چکیده
The functions of the gluon fragmentation into 3 P J quarkonium are calculated to order 2 s. With the recent progress in analysing quarkonium systems in QCD we show explicitly how the socalled divergence in the limit of the zero-binding energy, which is related to P-wave quarkonia, is treated correctly in the case of fragmentation functions. The obtained fragmentation functions satisfy explicitly at the order of 2 s the Altarelli-Parisi equation and when z ! 0 they behave as z 1 as expected. Some comments on the previous results are made.
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