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NLO perturbative QCD predictions for gamma gamma -> M+ M- (M=pi,K)

Goran Duplancic·Bene Nizic
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Abstract

We report the first complete leading-twist next-to-leading-order perturbative QCD predictions for the two-photon exclusive channels gamma gamma -> M+ M- (M=pi,K) at large momentum transfer. The asymptotic distribution amplitude is utilized as a candidate form for the nonperturbative dynamical input. Comparison of the obtained results with the existing experimental data does not provide sufficiently clear evidence to support the applicability of the hard-scattering approach at currently accessible energies.

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Goran Duplancic, Bene Nizic. 2006-09-06. NLO perturbative QCD predictions for gamma gamma -> M+ M- (M=pi,K). https://doi.org/10.1103/physrevlett.97.142003

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