Quasifree Photoabsorption on Neutron-proton Pairs in 3 He *
نویسندگان
چکیده
Three-body photodisintegration of 3 He is calculated in the photon energy range 200 – 400 MeV assuming quasifree absorption on np pairs both in initial quasideuteron and singlet configurations. The model includes the normal nucleonic current, explicit meson exchange currents and the ∆(1232)-isobar excitation. The total cross section is increased by a factor of about 1.5 compared with free deuteron photodisintegration. Well below and above the ∆ region also some spin observables differ significantly from the ones of free deuteron disintegration due to the more compressed wave function of the correlated np pairs in 3 He compared to the deuteron. The initial singlet state causes a significant change in the analyzing power A y. These differences could presumably be seen at the conjugate angles where two-body effects are maximized and where photoreactions could complement similar pion absorption experiments.
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