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arXiv · hep-ph/0108220

The annihilation of virtual photons into pseudoscalar mesons

M. Diehl·P. Kroll·C. Vogt
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Abstract

We investigate the possibility to constrain the pion distribution amplitude from the gamma* gamma* -> pi transition. For a surprisingly large range in the two photon virtualities we find that the transition form factor is essentially independent of the distribution amplitude. This in turn entails a parameter-free prediction of QCD. The gamma* gamma* -> eta, eta' form factors are also briefly discussed. We estimate that experimental studies might be feasible at the existing e+ e- experiments BaBar, Belle, and CLEO.

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M. Diehl, P. Kroll, C. Vogt. 2001-08-27. The annihilation of virtual photons into pseudoscalar mesons. https://doi.org/10.1007/s100520100830

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