Eur. Phys. J. C (2015) 75: 328
https://doi.org/10.1140/epjc/s10052-015-3552-0

Regular Article - Theoretical Physics

Impact of family-non-universal boson on pure annihilation and decays

¹ Department of Physics, Yantai University, Yantai, 264-005, China
² Wenjing College, Yantai University, Yantai, 264-005, China

^* e-mail: liying@ytu.edu.cn

Received: 3 March 2015
Accepted: 2 July 2015
Published online: 17 July 2015

Abstract

We study the and decays in the standard model and the family-non-universal model. Since none of the quarks in the final states is the same as the initial quark, these decay modes can occur only via power-suppressed annihilation diagrams. Despite the consistency of the standard model prediction with the available data, room remains for a light boson. Taking into account the contribution, we find that theoretical results for the branching fractions can better accommodate the data. With the relevant data, we also derive a constraint on the parameter space for the . Moreover, for , both the direct and the mixing-induced CP asymmetry are sensitive to the couplings between and fermions in the parameter spaces constrained by the data. The measurements at future experimental facilities, including the LHCb, Belle-II, and the proposed high energy collider, will provide us useful hints for direct searching for the light boson.