Determination of the πNN Form Factor from the Threshold Pion Production of pp Scattering
نویسنده
چکیده
It is shown that the threshold productions of π0pp, π+np and π+d from pp collisions can be consistently described by a model consisting of a pion s-wave rescattering and NN̄ pair-terms of heavy-meson exchanges. The large difference between σ(pp → π+d) and σ(pp → π+np) is understood from the orthogonality of the deuteron and the np scattering wave functions. In a calculation using the Paris potential to account for the initial and final NN interactions, it is found that the data can be best reproduced by using a soft πNN form factor with Λπ = 650 MeV for a monopole form. This is consistent with an earlier study of pion production in the ∆ excitation region. PACS numbers: 13.60.Le, 13.75.Cs
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