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arXiv · 0705.3229

Observation and Properties of L=1 B_1 and B_2* Mesons

D0 Collaboration·V. Abazov
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Abstract

Excited B mesons B_1 and B_2* are observed directly for the first time as two separate states in fully reconstructed decays to B+(*) pi-. The mass of B_1 is measured to be (5720.6 +- 2.4 +- 1.4) MeV/c^2 and the mass difference DeltaM between B_2* and B_1 is (26.2 +- 3.1 +- 0.9) MeV/c^2, giving the mass of the B_2* as (5746.8 +- 2.4 +- 1.7) MeV/c^2. The production rate for B_1 and B_2* mesons is determined to be a fraction (13.9 +- 1.9 +- 3.2)% of the production rate of the B+ meson.

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D0 Collaboration, V. Abazov. 2007-05-22. Observation and Properties of L=1 B_1 and B_2* Mesons. https://doi.org/10.1103/physrevlett.99.172001

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