Evidence for the Exclusive Decay B_c^± → J/ψπ^± and Measurement of the Mass of the B_c^± Meson

Authors

A. Abulencia, University of Illinois, Urbana
Kenneth A. Bloom, University of Nebraska-LincolnFollow
CDF Collaboration

Date of this Version

3-3-2006

Comments

Published by American Physical Society. Phys. Rev. Lett. 96, 082002 (2006). http://prl.aps.org. Copyright © 2006 American Physical Society. Permission to use.

Abstract

We report the first evidence for a fully reconstructed decay mode of the B_c^± meson in the channel B_c^± → J/ψπ^±, with J/ψ → μ⁺ μ^-. The analysis is based on an integrated luminosity of 360 pb^-1 in pp̅ collisions at 1.96 TeV center of mass energy collected by the Collider Detector at Fermilab. We observe 14.6 ± 4.6 signal events with a background of 7.1 ± 0.9 events, and a fit to the J/ ψπ^± mass spectrum yields a B_c^± mass of 6285.7 ± 5.3(stat) ± 1.2(syst) MeV/c². The probability of a peak of this magnitude occurring by random fluctuation in the search region is estimated as 0.012%.