6533b823fe1ef96bd127ea17

RESEARCH PRODUCT

Probing short-range nucleon-nucleon correlations with virtual photons at MAMI

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Abstract Nucleon-nucleon correlations were studied in two (e, e′pp) experiments. The first one, on 12C, was performed in close to 4π geometry at Ebeam = 705 MeV, ω = 225 MeV, and q = 412 MeV/c. The electrons were observed in a large-acceptance magnetic spectrometer in coincidence with protons detected in a BGO crystal ball. Missing energy and momentum, relative momentum and angular distributions were derived and compared with a facorised two-nucleon emision model. A G-matrix correlation function is favoured by the data. The second experiment was a high resolution study of the reaction 16O(e, e′pp)14C in super-parallel kinematics. Three magnetic spectrometers were used in coincidence at Ebeam = 855 MeV, ω = 215 MeV, q = 316 MeV/c. A missing momentum (pair momentum) range −100 MeV/c ≤ Pm ≤ 450 MeV/c was sampled. Two-hole states were preferentially excited, with an energy resolution of 500 keV. Their momentum distributions are compared with unfactorised model calculations which make use of realistic NN potentials.