https://doi.org/10.1051/epjconf/201920401015
Δ-Isobar contribution to the pion production in the reaction pp → {pp}sπ0
1 Laboratory of Nuclear Problems, JINR, RU-141980 Dubna, Russia
2 Department of Physics, M.V. Lomonosov Moscow State University, RU-119991 Moscow, Russia
3 Dubna State University, RU-141980 Dubna, Russia
* e-mail: uzikov@jinr.ru
Published online: 3 April 2019
ANKE@COSY data on the cross section of the reaction pp → {pp}sπ0, where {pp}s is the proton pair in the 1S 0 state at small excitation energy Epp = 0 – 3 MeV, obtained at beam energies 0.5 - 2.0 GeV are analyzed within the one-pion exchange model. The model involves the subprocess π0 p → π0 p and accounts for the final state pp-interaction. A broad maximum observed in the cross section of the reaction pp → {pp}sπ0 at 0.5 - 1.4 GeV in the forward direction is explained by this model as a dominant contribution of the isospin 
in the π0 p-scattering. The second bump in data at 2 GeV is underpredicted within this model by one order of magnitude. An explicit excitation of the Δ(1232)-isobar using the box-diagram is also considered in the region of the first maximum.
© The Authors, published by EDP Sciences, 2019
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