ar X iv : h ep - p h / 01 10 31 9 v 1 2 4 O ct 2 00 1 Bottom Quark Fragmentation in Top Quark Decay
نویسندگان
چکیده
We study the fragmentation of the b quark in top decay in NLO QCD, within the framework of perturbative fragmentation, which allows one to resum large logarithms ∼ log(m 2 t /m 2 b). We show the b-energy distribution, which we compare with the exact O(α S) result for a massive b quark. We use data from e + e − machines in order to describe the b-quark hadronization and make predictions for the energy spectrum of b-flavoured hadrons in top decay. We also investigate the effect of NLL soft-gluon resummation in the initial condition of the perturbative fragmentation function on parton-and hadron-level energy distributions.
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