Reconstruction of semileptonic b→u decays

doi:10.1016/0370-2693(91)90251-K

Physics Letters B

Volume 255, Issue 2, 7 February 1991, Pages 297-304

https://doi.org/10.1016/0370-2693(91)90251-K Get rights and content

Abstract

Using the ARGUS detector at the e⁺ e⁻ storage ring DORIS II at DESY we have updated our result on charmless semileptonic B decays and searched for direct evidence for b→u transitions through reconstruction of complete events. This approach has successfully identified two ϒ (4S) events which contain B meson decays to a non-charm final state. In one case, a B⁰ meson is found in the channel $π^{+} μ^{−} ν$ , while in the other a decay B⁺→ωμ⁺ν is seen. These events show that the previously observed signal of charmless semileptonic B decays is due to b→u transitions from which we obtain $| V_{ub} V_{cb} | = 0.11±0.012$ using the model of Altarelli et al.

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¹: Supported by the German Bundesministerium für Forschung und Technologie, under contract number 054DO51P.

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Reconstruction of semileptonic b→u decays

Abstract

Phys. Lett. B

Phys. Lett. B

Nucl. Instrum. Methods A

Nucl. Phys. B

Phys. Lett. B

DESY report DESY 89-096

Phys. Lett. B

Phys. Rev. Lett.