The cross section for the 12C(γ, π+p) reaction was measured in the range of the △(1232) isobar. The data were analyzed using the models taking into account the nucleon and isobaric degrees of freedom of the 12C nucleus. The conclusion is drawn that in the large-momentum transfer range the π+p pairs are produced in the course of the direct knocking-out of △++ isobar from the nucleus. The probability of finding the △ isobar in the ground-state 12C nucleus is estimated at 0.018 ± 0.005 △ isobars per nucleon.
ASJC Scopus subject areas
- Physics and Astronomy(all)