Measurement of the ratio of branching fractions B(B±-->J/ psi pi ±)/B(B±-->J/ psi K±)

• Main Authors: Paus, Christoph M. E. (Contributor), Miles, Christopher J. (Contributor), Makhoul, K. (Contributor), Leonardo, N. (Contributor), Kravchenko, I. (Contributor), Knuteson, Bruce O. (Contributor), Iyutin, Boris (Contributor), Henderson, C. (Contributor), Hahn, Kristian Allan (Contributor), Choudalakis, Georgios (Contributor), Bolshov, Arkadiy (Contributor), Belloni, Alberto (Contributor), Bauer, Gerry P. (Contributor), Klute, Markus (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Physics (Contributor), Massachusetts Institute of Technology. Laboratory for Nuclear Science (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2010-03-03T16:48:25Z.
• Subjects: Article
• Online Access: Get fulltext

 We report a measurement of the ratio of branching fractions of the decays B[superscript ±]→J/ψπ[superscript ±] and B[superscript ±]→J/ψK[superscript ±] using the CDF II detector at the Fermilab Tevatron Collider. The signal from the Cabbibo-suppressed B[superscript ±]→J/ψπ[superscript ±] decay is separated from B[superscript ±]→J/ψK[superscript ±] using the B[superscript ±]→J/ψK[superscript ±] invariant mass distribution and the kinematical differences of the hadron track in the two decay modes. From a sample of 220  pb[superscript -1] of pp̅ collisions at √s=1.96  TeV, we observe 91±15 B[superscript ±]→J/ψπ[superscript ±] events together with 1883±34 B[superscript ±]→J/ψK[superscript ±] events. The ratio of branching fractions is found to be B(B[superscript ±]→J/ψπ[superscript ±])/B(B[superscript ±]→J/ψK[superscript ±])=(4.86±0.82(stat)±0.15(syst))%.