Eur. Phys. J. C (2006) 48: 401-411
https://doi.org/10.1140/epjc/s10052-006-0029-1

Theoretical Physics

Large strong phases and CP violation in the annihilation processes B̄⁰→K⁺K^-, K^*±K^∓, K^*+K^*-

¹ Institute of Theoretical Physics, Chinese Academy of Science, Beijing, 100080, P.R. China
² Graduate School, Chinese Academy of Science, Beijing, 100039, P.R. China
³ Department of Physics, Henan Normal University, Xinxiang, Henan, 453007, P.R. China

^* e-mail: ylwu@itp.ac.cn

Received: 17 April 2006
Revised: 6 July 2006
Published online: 24 October 2006

Abstract

The strong phases and CP violation in the rare B̄⁰→K⁺K^-, K^*±K^∓, K^*+K^*- decays are investigated. As these decays proceed only via annihilation type diagrams in the standard model (SM), a dynamical gluon mass is introduced to avoid the infrared divergence in the soft endpoint regions. The Cutkosky rule is adopted to deal with a physical-region singularity of the on-mass-shell quark propagators, which leads to a big imaginary part and hence a large strong phase. As a consequence, large CP asymmetries are predicted in those decay modes due to a big interference between the annihilation amplitudes from penguin and tree operators, which may be tested in future more precise experiments.