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Evidence for the exclusive decay Bc+- to J/psi pi+- and measurement of the mass of the Bc meson

CDF Collaboration·A. Abulencia
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Abstract

We report first evidence for a fully reconstructed decay mode of the B_c^{\pm} meson in the channel B_c^{\pm} \to J/psi π^{\pm}, with J/psi \to mu^+mu^-. The analysis is based on an integrated luminosity of 360 pb$^{-1} in p\bar{p} collisions at 1.96 TeV center of mass energy collected by the Collider Detector at Fermilab. We observe 14.6 \pm 4.6 signal events with a background of 7.1 \pm 0.9 events, and a fit to the J/psi pi^{\pm} mass spectrum yields a B_c^{\pm} mass of 6285.7 \pm 5.3(stat) \pm 1.2(syst) MeV/c^2. The probability of a peak of this magnitude occurring by random fluctuation in the search region is estimated as 0.012%.

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CDF Collaboration, A. Abulencia. 2006-02-27. Evidence for the exclusive decay Bc+- to J/psi pi+- and measurement of the mass of the Bc meson. https://doi.org/10.1103/physrevlett.96.082002

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