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arXiv · 2101.11521

Angular analysis of bottom-flavored hadron production in semileptonic decays of polarized top quarks

Bernd A. Kniehl·S. Mohammad Moosavi Nejad
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Abstract

We study the inclusive production of bottom-flavored hadrons from semileptonic decays of polarized top quarks at next-to-leading order in QCD using fragmentation functions recently determined from a global fit to $e^+e^-$ data. We provide the relevant differential decay widths at parton level in analytic form. These results fill an important gap in the theoretical interpretation of recent measurements of the top-quark polarization and the $t\bar{t}$ spin correlations using dilepton final states in proton-proton collisions at the CERN Large Hadron Collider. As an illustration, we study the distributions in the scaled bottom-hadron energy of the polarized-top-quark decay widths for different $W$-boson helicities.

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Bernd A. Kniehl, S. Mohammad Moosavi Nejad. 2021-01-27. Angular analysis of bottom-flavored hadron production in semileptonic decays of polarized top quarks. https://doi.org/10.1103/physrevd.103.034015

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