A striking similarity was observed in the spectra of the (.pi./sup +/,p) and 800-MeV (p,d) reactions on the same target this result implies a similar mechanism for the two reactions. It is, however, unclear whether this failure is due to a fundamental inadequacy of the model or improper treatment of details in the calculations. Calculations employing a one-nucleon model more ยป of the reaction mechanism similar to the model successfully used for the (p,d) reaction are unable to account for transitions in the (.pi./sup +/,p) reaction. The first high-resolution measurements of the (.pi./sup +/,p) reaction were also performed on /sup 6/Li, /sup 7/Li, /sup 12/C, and /sup 13/C at pion bombarding energies on and off the pion-nucleon resonance. Explicit calculations were performed to confirm this for several examples. The relative intensities of the other levels observed suggest that coupled-channels mechanisms play an important role for some of these states. States that have never been seen before were strongly populated in the high excitation region (up to 25 MeV) of some of the residual nuclei. The calculations are also sensitive to the neutron single-particle wave function, in accordance with the expectation that the high-momentum components of this wave function are probed at higher bombarding energies. A specific counter example to the two-nucleon model of the reaction mechanism is suggested. A modified version of the one-nucleon model successfully describes the magnitude and angular dependence of almost all of the transitions observed. 400 keV) attained was sufficient to observe many discrete levels in each of the residual nuclei. The (p,d) reaction was studied for the first time at 800 MeV on seven targets ranging from /sup 7/Li to /sup 40/Ca.
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