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Direct measurement of the pion valence quark momentum distribution, the pion light-cone wave function squared

E791 Collaboration·E. M. Aitala
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Abstract

We present the first direct measurements of the pion valence quark momentum distribution which is related to the square of the pion light-cone wave function. The measurements were carried out using data on diffractive dissociation of 500 GeV/c $π^-$ into di-jets from a platinum target at Fermilab experiment E791. The results show that the $|q\bar {q}>$ light-cone asymptotic wave function, which was developed using perturbative QCD methods, describes the data well for $Q^2 \sim 10 ~{\rm (GeV/c)^2}$ or more. We also measured the transverse momentum distribution of the diffractive di-jets.

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E791 Collaboration, E. M. Aitala. 2000-10-17. Direct measurement of the pion valence quark momentum distribution, the pion light-cone wave function squared. https://doi.org/10.1103/physrevlett.86.4768

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