https://doi.org/10.1140/epjc/s10052-010-1280-z
Regular Article - Theoretical Physics
The cross section of the process e ++e −→J/ψ+η c within the QCD light-cone sum rules
1
Department of Modern Physics, University of Science and Technology of China, Hefei, 230026, P.R. China
2
Institute of High Energy Physics and Theoretical Physics Enter for Science Facilities, Chinese Academy of Sciences, Beijing, 100049, P.R. China
3
Department of Physics, Chongqing University, Chongqing, 400044, P.R. China
4
Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190, P.R. China
* e-mail: sunyj@ihep.ac.cn
Received:
11
November
2009
Revised:
15
January
2010
Published online:
9
March
2010
We calculate the cross section of the exclusive process e ++e −→J/ψ+η c at the leading order approximation within the QCD light-cone sum rules approach. It is found that the form factor F VP(V=J/ψ,P=η c ) depends mainly on the behavior of the twist-2 distribution amplitude of the η c meson at the scale of this process. Thus in order to obtain a reliable estimation of the cross section, it is important to have a realistic distribution amplitude of the η c meson and to deal with the evolution of the distribution amplitude to the effective energy scale of the process. Our results show that one can obtain a compatible prediction with the Belle and BaBar experimental data.
© Springer-Verlag / Società Italiana di Fisica, 2010