https://doi.org/10.1140/epjc/s10052-007-0245-3
Regular Article - Theoretical Physics
Determination of the η and η′ mixing angle from the pseudoscalar transition form factors
1
Institute of High Energy Physics, Chinese Academy of Sciences, P.O. Box 918(4), Beijing, 100039, P.R. China
2
Institute of Theoretical Physics, Chinese Academy of Sciences, P.O. Box 2735, Beijing, 100080, P.R. China
3
Department of Physics, Chongqing University, Chongqing, 400044, P.R. China
* e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Received:
1
December
2006
Published online:
13
March
2007
Abstract
The possible range of the η–
mixing angle is determined from the transition form factors Fηγ(Q2) and 
with the help of up-to-date experimental data. For this purpose, the quark-flavor mixing scheme is adopted and the pseudoscalar transition form factors are calculated in the framework of light-cone pQCD, in which the transverse-momentum corrections and the contributions beyond the leading Fock state have been carefully taken into consideration. We construct a phenomenological expression to estimate the contributions to the form factors beyond the leading Fock state, based on their asymptotic behavior at Q2→0 and 
. By taking the quark-flavor mixing scheme, our results lead to 
, where the first error comes from the experimental uncertainty and the second error from the uncertainties of the parameters of the wavefunction. The possible intrinsic charm component in η and is discussed, and our present analysis also disfavors a large intrinsic charm component in η and , e.g. 
.
© Springer-Verlag Berlin Heidelberg, 2007
