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QCD-corrected spin analysing power of jets in decays of polarized top quarks

A. Brandenburg·Z. G. Si·P. Uwer
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Abstract

We present results for the differential distributions of jets from non-leptonic decays of polarized top quarks within the Standard Model, including QCD radiative corrections. Our work extends existing results which are only available for semileptonic top quark decays at the parton level. For $t(\uparrow)$ -> b-jet + 2 light jets we compute in particular the QCD-corrected top-spin analysing power of the b-quark jet and the least energetic light jet. The dependence of the results on the choice of the jet recombination scheme is found to be small. In addition we compute the spin analysing power of the thrust axis. Our results constitute a so far missing ingredient to analyse top quark production and subsequent non-leptonic decay at next-to-leading order in alpha_s, keeping the full information on the top quark polarization.

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A. Brandenburg, Z. G. Si, P. Uwer. 2002-05-02. QCD-corrected spin analysing power of jets in decays of polarized top quarks. https://doi.org/10.1016/s0370-2693(02)02098-1

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