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The pion momentum distributions (MDs) in four channels of virtual decay p→B+π, B = N, Δ, N 1/2-(1535), N 1/2+(1440) are calculated in two models, the microscopic model of 3 P 0 scalar q−q fluctuation with the pion as a composite q−q-system and the chiral semi-microscopic model of πq interaction with the pion as a structureless Goldstone boson. The results of the above models are similar for the baryon states B = N, Δ, N 1/2-(1535) but are rather different for the Roper resonance N 1/2+(1440) which corresponds to excitation of two oscillator quanta in the nucleon. The experimental investigation of pion MDs by means of the reaction of quasi-elastic knockout of pion by an electron of a few GeV energy p(e, e′ π)B may be very suitable for Jefferson Laboratory, Virginia (JLab).
 A. Le Yaouanc, L. Oliver, O. Péne, and J. Raynal: “Strong decay of Ψ'(4.028) as a radial excitation of charmonium”, Physics Letters, Vol. 71B, (1977), pp. 397–399; A. Le Yaouanc, L. Oliver, O. Péne, and J. Raynal: “Why is Ψ(4.414) so narrow?”, Physics Letters, Vol. 72B, (1977), pp. 57–61.
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