Eur. Phys. J. C (2007) 49: 651-656
https://doi.org/10.1140/epjc/s10052-006-0151-0

Regular Article - Theoretical Physics

Annihilation contributions in B→K₁γ decay in next-to-leading order in LEET and CP-asymmetry

National Centre for Physics and Department of Physics, Quaid-i-Azam University, Islamabad, Pakistan

^* e-mail: jamil@ncp.edu.pk

Received: 29 April 2006
Revised: 22 May 2006
Published online: 2 December 2006

Abstract

The effect of weak annihilation and u-quark penguin contribution on the branching ratio B→K₁γ at next-to-leading order of α_s are calculated using the LEET approach. It is shown that the value of the LEET form factor remains the same in the range of the unitarity triangle phase α favored by the standard model. The CP-asymmetry for the above mentioned decay has been calculated, and its suppression due to the hard-spectator correction has also been incorporated. In addition, the sensitivity of the CP-asymmetry on the underlying parameters has been discussed.