Study of Direct CP Violation in B^± → J/ψK^±(π^±) Decays

Authors

V. M. Abazov, Joint Institute for Nuclear Research, Dubna, Russia
Gregory R. Snow, University of Nebraska-LincolnFollow
Kenneth A. Bloom, University of Nebraska-LincolnFollow
D0 Collaboration

Date of this Version

May 2008

Comments

Published by American Physical Society. Phys. Rev. Lett. 100, 211802 (2008). http://prl.aps.org. Copyright © 2008 American Physical Society. Permission to use.

Abstract

We present a search for direct CP violation in B^±→J/ψK^±(π^±) decays. The event sample is selected from 2.8 fb^-1 of pp collisions recorded by D0 experiment in run II of the Fermilab Tevatron Collider. The charge asymmetry A_CP(B⁺→J/ψK⁺) =+0.0075 ±± 0.0061(stat) ± 0.0030(syst) is obtained using a sample of approximately 40 000 B^±→J/ψK^±decays. The achieved precision is of the same level as the expected deviation predicted by some extensions of the standard model. We also measured the charge asymmetry A_CP(B⁺→J/ψK⁺) = -0.09 ± 0.08(stat) ± 0.03(syst).