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The first ({ital p},{ital n}) polarization-transfer measurements for delta production on a nuclear target are presented for the {sup 12}C({ital p}{searrow},{ital n}{searrow}) reaction at 0{degree} and 795 MeV. Polarization observables are used to extract the spin-longitudinal, spin-transverse, and spin-independent partial cross sections. In the spin-longitudinal channel, fair agreement is found between experiment and a model which includes a strongly attractive residual interaction. A large unexpected enhancement in the spin-transverse cross section is observed. {copyright} {ital 1996 The American Physical Society.}

Breakup of 63-MeV and 42-MeV {sup 7}Li near the {alpha}-{ital t} threshold is examined from the astrophysical point of view. A new approach is made to extract indirectly astrophysical {ital S} factors. The {ital S} factors are compared with those deduced from radiative-capture measurements. It is shown that the energy dependence favors the recent capture data of Schroeder {ital et} {ital al}.

It is shown that massive transfer reactions emitting energetic light particles can be described in terms of two-step processes, in which breakup of the projectile takes place first, followed by an absorption of the massive partner of the broken-up pair by the target.

Two very different types of angular distributions, one having a normal bell shape and the other being much more constant with angle were observed in the reaction $^{144}\mathrm{Nd}$($^{12}\mathrm{C}$, $^{14}\mathrm{C}$) for two well-known ${2}^{+}$ states of $^{142}\mathrm{Nd}$. The fits to these angular distributions using the distorted-wave Born approximation and/or coupled-channel Born approximation confirms the conclusion that the data give definite evidence for the importance of multistep processes. A comparison with the reaction $^{144}\mathrm{Nd}(p, t)$ is also discussed.

Continuum cross sections and spin polarizations of /sup 12/B produced in the reaction /sup 197/Au(/sup 19/F,/sup 12/B) induced by 186-MeV/sup 19/F were measured. The observed data were reproduced very well in terms of a distorted-wave Born-approximation theory, indicating that this reaction transferring as many as seven nucleons proceeds as a direct process.

Alpha-transfer reactions (/sup 20/Ne,/sup 16/O), (/sup 14/N,/sup 10/B), and (/sup 13/C,/sup 9/Be) on a /sup 40/Ca target were studied at 262, 153, 149 MeV, respectively. Analysis in terms of the direction-reaction theory reproduced the observed continuum spectra and angular distributions well, except for the cross section of the reaction (/sup 20/Ne,/sup 16/O) at small angles, which is attributed to a projectile breakup process.

The polarization of /sup 12/B produced in the reaction /sup 100/Mo(/sup 14/N,/sup 12/B)/sup 102/Ru is explained in a fully quantum mechanical way. It is found that recoil plays a decisive role.

We compare the differential cross section at a proton energy of 39.8 MeV for the transition ${\mathrm{Ne}}^{22}(p,t){\mathrm{Ne}}^{20}$ (${2}^{\ensuremath{-}}$, 4.97 MeV), which is forbidden by the usual selection rules for a single-step process, with a coupled-channel Born-approximation calculation using rotational wave functions of the adiabatic form. The calculated results are in good agreement with the experimental data.