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arXiv · hep-ph/0110319

Bottom Quark Fragmentation in Top Quark Decay

Abstract

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 $\sim\log (m_t^2/m_b^2)$. We show the b-energy distribution, which we compare with the exact ${\cal O} (α_S)$ 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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BibTeXRIS

Gennaro Corcella, Alexander D. Mitov. 2001-10-24. Bottom Quark Fragmentation in Top Quark Decay. https://doi.org/10.1016/s0550-3213(01)00639-3

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