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First measurement of the double-inclusive B/Bbar hadron energy distribution in e+e- annihilations, and of angle-dependent moments of the B and Bbar energies

SLD Collaboration·Koya Abe
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Abstract

We have made the first measurement of the double-inclusive B/Bbar energy distribution in e+e- annihilations, using a sample of 400,000 hadronic Z0 decay events recorded in the SLD experiment at SLAC between 1996 and 1998. The small and stable SLC beam spot and the CCD-based vertex detector were used to reconstruct B/Bbar decay vertices with high efficiency and purity, and to provide measurements of the kinematic quantities used to calculate the B energies in this novel technique. We measured the B/Bbar energies with good efficiency and resolution over the full kinematic range. We measured moments of the scaled energies of the B and Bbar hadrons vs. the opening angle between them. By comparing these results with perturbative QCD predictions we tested the ansatz of factorisation in heavy-quark production. A recent next-to-leading order calculation reproduces the data.

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SLD Collaboration, Koya Abe. 2003-09-18. First measurement of the double-inclusive B/Bbar hadron energy distribution in e+e- annihilations, and of angle-dependent moments of the B and Bbar energies. https://doi.org/10.1016/j.physletb.2003.10.057

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