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Soft-Gluon Resummation for Bottom Fragmentation in Top Quark Decay

Matteo Cacciari·Gennaro Corcella·Alexander D. Mitov
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Abstract

We study soft-gluon radiation in top quark decay within the framework of perturbative fragmentation functions. We present results for the b-quark energy distribution, accounting for soft-gluon resummation in both the MSbar coefficient function and in the initial condition of the perturbative fragmentation function. The results show remarkable improvement and the b-quark energy spectrum in top quark decay exhibits very little dependence on factorization and renormalization scales. We present some hadron-level results in both x_B and moment space by including non-perturbative information determined from e+e- data.

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Matteo Cacciari, Gennaro Corcella, Alexander D. Mitov. 2003-01-21. Soft-Gluon Resummation for Bottom Fragmentation in Top Quark Decay. https://doi.org/10.1088/1126-6708%2F2002%2F12%2F015

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