The Quasifree Knockout of Protons and Deuterons from Calcium, Oxygen, and Carbon Targets Induced by 150 Mev Polarized Protons.
The ('40)Ca(p,2p) and ('16)O and ('12)C(p,pd) reactions induced by 150 MeV polarized protons were studied in experiments conducted at the Indiana University Cyclotron Facility. The experiments employed quasifree (zero recoil) geometries. Energy sharing distributions and analyzing power distributions were extracted from the data and compared to Distorted Wave Impulse Approximation (DWIA) calculations. Energy sharing distribution calculations for the ('40)Ca(p,2p)('39)K reaction are in fairly good agreement with the data, the agreement being better for L = 0 transitions than for L = 2 transitions. Extracted spectroscopic factors for low-lying states are in reasonable agreement with shell model calculations and previous experimental results. Analyzing power calculations for the low-lying states are in good agreement with the data, except in the L = 0 transition to the 2.53 MeV state of ('39)K where virtually the entire analyzing power results from spin-orbit effects. Analyzing power data suggest that 1d(,5/2) strength can be seen in the 11 MeV to 15 MeV region of excitation energy as well as in the 5 MeV to 10 MeV region. Analyzing powers for excitation energies larger than 15 MeV are close to zero, suggesting the dominance of multi-step events. The energy sharing distributions calculated for the ('16)O(p,pd)('14)N(g.s.) and ('12)C(p,pd)('10)B (g.s. + 0.717 MeV) transitions are generally in qualitative agreement with the data, however, the shape and magnitude of the calculated energy sharing distributions varied somewhat with the optical model and bound state parameters used. Analyzing powers in the (p,pd) reactions are in good agreement with analyzing powers for free p + d scattering, giving evidence to the credibility of the quasifree knockout mechanism. The ('40)Ca(p,2p) and ('12)C(p,pd) data were also taken at a number of quasifree angles in order to test the validity of the factorized DWIA. In both cases the data are encouraging but inconclusive. In the process of the experiments some ('16)O(p,2p), ('12)C(p,2p), and ('40)Ca(p,pd) data were also obtained and analyzed.
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- Physics: Nuclear