The Photon-pion Transition Form Factor for Virtual Photons
نویسنده
چکیده
We discuss the photon to meson transition form factor for virtual photons, which can be measured in ee collisions. We demonstrate that this form factor is independent of the shape of the meson distribution amplitude over a wide kinematical range. This leads to a parameter-free prediction of perturbative QCD to leading twist accuracy, which has a status comparable to the famous leading-twist prediction of the cross section ratio R.
منابع مشابه
The Photon-pion Transition Form Factor for Virtual Photons
We discuss the photon to meson transition form factor for virtual photons, which can be measured in ee collisions. We demonstrate that this form factor is independent of the shape of the meson distribution amplitude over a wide kinematical range. This leads to a parameter-free prediction of perturbative QCD to leading twist accuracy, which has a status comparable to the famous leading-twist pre...
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تاریخ انتشار 2001