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Cxamow-Teller strength in the " Ca{p,n) Sc reaction was studied at 134 and 160 MeV. Neutron energy spectra were measured by the time-of-flight technique with resolutions of about 320 and 460 keV, respectively. The cross sections reported at 160 MeV are increased (by a factor of about 1.4) from results reported previously. The 1+ Gamow-Teller strength is observed to be split into a lowlying state at E"=2.52 MeV, the Cxamow-Teller giant resonance in a complex of states between 4.5 and 14.5 MeV, and a single T=4 state at 16.8 MeV. The general distribution of the 1+ strength in Sc is in good agreement with a shell-model prediction. The total 1+ strength observed in discrete states amounts to 43% of the simple Gamow-Teller sum rule, relative to the observed 0+, Fermi strength assumed to be concentrated into the isobaric analog state at 6.67 MeV. Consideration of the Al =0 contributions to the background under the Gamow-Teller giant resonance and of the non-quasifree scattering contributions to the continuum (up to about 30 MeV) increases this fraction to about 70%%uo. Possible Ciamow-Teller strength in the quasifree scattering contributions to the continuum is discussed.

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The~Ca{p,n) Sc reaction was studied at 134 MeV. Neutron energy spectra were measured by the time-of-Aight technique with resolutions of 220 keV at angles from 0' to 41' and 415 keV out to 62'. The 2,3,4,5 band of states based on the (f7qs, dqq2) lplh structure was observed at low excitation energies, in good agreement with known analog states in~C a and K. The shapes of the cross-section and analyzing-power angular distributions are in good agreement with distorted-w'ave impulse-approximation calculations using simple 1p1h (Tamm-Dancoff approximation) shell-model wave functions. A relatively strong transition to a state at E"=2. 3 MeV with L =3 is identified tentatively as a 4 state with the predominant 1p1h structure (1f7qt, 2s~qi). The excitation of the ( T = 1) 6 (f7',dqq2) stretched state is observed near E, =7 MeV, fragmented over approximately 3MeV. The normalization factor required to make a distorted-wave impulse-approximation calculation agree in magnitude with the 6 excitation is 0.35, which is larger than the normalization factor for this excitation in mass 28, analyzed in a similar manner. The I. =1 giant resonance is observed to be centered near E"=10MeV with a width (full width at half maximum) of about 5 MeV, and a distorted-eave impulse-approximation normalization factor of 0.16. Two 1 excitations are observed at E"=2.7 and 4.3 MeV which indicate directly the presence of ground-state correlations in the Ca target. The fact that the analog of the higher 1+ excitation is not seen in inelastic electron scattering indicates strong interference between spin and orbital current contributions. The effect of ground-state correlations on the 1plh wave functions was investigated by performing calculations which allowed multiparticle-multihole correlations in the d3qt and f7/2 orbitals. The distorted-wave impulse-approximation normalization factors obtained with these wave functions were found to increase by a factor of about 2 relative to those obtained with~C a assumed to be a closed core.

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