Speaker
Description
The annihilation or production process $e^++e^-\rightarrow
\rho^+ + \rho^- $ is studied with respect to the
universal perturbative QCD (pQCD) predictions. Sub-leading contributions
are considered together with the universal leading pQCD amplitudes such that
the matrix elements of the $\rho$-meson electromagnetic current satisfy
the constraint from the light-front angular condition. The data from the
BaBar collaboration for the time-like $\rho$-meson
form factors at $\sqrt{s}=10.58$ GeV puts a stringent
test to the onset of asymptotic pQCD behaviour. The $e^++e^-\rightarrow
\rho^+ +\rho^- $ cross-section for $s$ between 60 GeV$^2$ and
160 GeV$^2$ is predicted where the sub-leading contributions are still considerable.
References:
1. B. Aubert, et. al., Babar collaboration, Phys. Rev. D78 (2008) 071103
2. J. P. B. C. de Melo, C. R. ji and T. Frederico, Phys. Lett. B 763 (2016) 87.