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Search for exclusive decays of the Lambda_b baryon at LEP-1

Winfried A. Mitaroff
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Abstract

A search for fully reconstructed Lambda_b baryons was performed, using about 3.5x10^6 hadronic Z0 decays acquired by the DELPHI detector at LEP-1. Two event candidates were found in the colour-suppressed decay channel J/psi Lambda, and four in the colour-allowed channels Lambda_c pi/a1, with an estimated background of 0.25 and 1.05 events, respectively. Measurements of the Lambda_b mass yield (5612.1 +- 21.2 +- 6.0) MeV and (5610 +- 24 +- 16) MeV, respectively, and are consistent with the world average value of PDG.

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Winfried A. Mitaroff. 2002-09-06. Search for exclusive decays of the Lambda_b baryon at LEP-1. https://arxiv.org/abs/hep-ex/0208020

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