The polarization of protons from the ${}_{}{}^7{}_{}{}^{}\mathrm{Li}({}_{}{}^3{}_{}{}^{}\mathrm{He},\overrightarrow{\mathrm{p}}){}_{}{}^9{}_{}{}^{}\mathrm{Be}$ reaction was measured at four laboratory angles between 70° and 85° at a bombarding energy of 14 MeV. The results are in marked disagreement with earlier reported measurements performed under similar conditions. A comparison between our polarization measurements and previous analyzing power measurements for the inverse reaction initiated by polarized protons shows no evidence for violation of time-reversal invariance as claimed.

The theory of inelastic breakup reaction formulated in terms of the post form distorted wave Born approximation has been tested directly against a recent experiment in which inelastic breakup cross section for the ${}_{}{}^{165}{}_{}{}^{}\mathrm{Ho}$(${}_{}{}^3{}_{}{}^{}\mathrm{He}$,d) breakup reaction has been determined via (particle, $\gamma$) coincidence measurements. The calculated elastic and inelastic cross sections are in good agreement with those obtained experimentally. The dominant values of the angular momenta transferred to the target during the inelastic breakup process lie between 5 and 12 $\hslash$ units, which indicates that these reactions may be used to selectively populate high spin states in the nuclei.

A microscopic optical potential, which is calculated nonrelativistically with a density-dependent effective force, is used to calculate cross sections, polarizations, and spin-rotation functions for elastic proton scattering from ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ at 160 and 497 MeV. At 160 MeV, the agreement to the data is comparable to phenomenological fits, and the spin rotation can be used to distinguish between microscopic and Woods-Saxon potentials. A good fit to the spin-rotation function results at 497 MeV, whereas the polarization data are not well reproduced.

The ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$(p,${\mathrm{p}}_0$), (p,${\mathrm{p}}_1$), (p,${\mathrm{p}}_2$), (p,${\alpha }_0$), and (p,${\alpha }_1$) excitation functions were measured at 90°, 105°, 135°, and 160° in the range $E_{\mathrm{p}}=1.85-3.05\mathrm{}$ MeV with an overall resolution of 350-400 eV full width at half maximum. Resonance parameters were extracted for 73 resonances with a multilevel, multichannel $R$-matrix analysis code; these parameters include resonance energy, total angular momentum, partial widths, and channel spin and orbital angular momentum mixing ratios. Eight analog states were identified, and the Coulomb displacement energies and spectroscopic factors were calculated. The values of the $s$-wave strength functions for $J=2\mathrm{} \mathrm{and} 3$ are $S_{J=2\mathrm{}}=0.042\mathrm{}$ and $S_{J=3\mathrm{}}=0.012\mathrm{}$. The spectroscopic strengths of the $J^{\pi }=4^{-}, 5^{-}, \mathrm{and} 6^{-}$ particle-hole states are presented and compared with other results.

We have studied the bound-state solutions of a system of two particles of mass $M$ which do not interact among themselves but which interact attractively with a third particle of mass $\mu$ as a function of the ratio $\frac{M}{\mu }$. In the limit $\frac{M}{\mu }\to 0$, the solution of the system is well known since it corresponds to the problem of two independent particles in a well. We point out that in the limit $\frac{M}{\mu }\to \infty$ the solution is also very simple, and it corresponds to having the two particles of mass $M$ fixed at the same point in space. We have found that the three-body binding energy tends to be proportional to the square of the range of the two-body interaction in momentum space, and that the sensitivity of the binding energy with respect to off-shell variations of the two-body amplitude increases when $\frac{M}{\mu }$ increases.

Cross sections for the ($\alpha$,d) reaction on ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ were measured at $E_{\alpha }=34.9\mathrm{}$ MeV in the range of excitation energies up to 11 MeV in ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ and up to 13 MeV in ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$. The angular distributions were compared to calculations with the zero-range distorted-wave Born approximation with the assumption of a deuteron-cluster transfer. On the basis of the assumption that the transferred two nucleons are weakly coupled to the target nuclei, correspondences between the transferred angular momenta and the strengths for the two-nucleon pairs were found for the residual nuclei ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ and ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$. Effects of the $0d_{\frac{3}{2}}$ shell and a necessity for the tensor force are discussed in terms of the two-nucleon configurations $d_{\frac{3}{2}}{p}_{\frac{1}{2}}$ and ${\left(d_{\frac{5}{2}}\right)}^2$, respectively.

In this paper, the problems of nonorthogonality and possible overcompleteness in the resonating group method equations are treated by explicitly symmetrizing previously developed distinguishable-particle methods. It is shown that the orthogonalized resonating group method equations are equivalent to the two-cluster-subspace projections of a symmetrized set of multiparticle scattering equations with distortion operators. The result of the analysis is the conversion of the resonating group method to an in-principle, convergeable approximation scheme. Corrections to the resonating group method from three-cluster contributions are briefly discussed.

The angular correlations and missing energy spectrum in quasifree electron scattering are studied in the unfactorized distorted wave impulse approximation. The present approach, in the nonrelativistic description, effectively includes the finer aspects of the process, namely the off-energy-shell effect and the spin-orbit coupling, which are neglected or approximated in the usual factorization methods. A comparative study between the factorized and unfactorized methods reveals that the unfactorized cross section not only accounts for the absolute value but also a possible asymmetry in its distribution. The study of the off-shell influence on spherical and nonspherical nuclei indicates that the off-shell effect is to increase with the increase of nuclear deformation.

Elastic neutron scattering from ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ has been measured at 22.0 and 24.0 MeV and remeasured at 7.0 and 20.0 MeV with greatly improved precision. The present results and other neutron data in the energy range 7—50 MeV are analyzed in terms of a conventional, local optical model potential with the aim of studying energy dependence of the potential well depths. We find that the very detailed measurements of the present work made unusual demands on the geometrical parameters of the model. Improvements, if any, resulting from extension of the optical model parametrization to include a real surface term and imaginary spin-orbit term are tested. Concurrently with the elastic scattering experiments, inelastic scattering to the $3^{-}$ state at 2.615 MeV was measured at 7.0, 20.0, and 22.0 MeV. A distorted-wave Born approximation analysis is made of these data to extract octupole deformation parameters.

Primary neutron capture $\gamma$ rays have been studied from 86 neutron resonances in ${}_{}{}^{167}{}_{}{}^{}\mathrm{Er}$ in the energy range 5-600 eV. The spins of these resonances were assigned as $I=3\mathrm{} or 4$ on the basis of the intensity ratios of suitable pairs of low-energy $\gamma$ rays. The measured intensities of the high-energy primary $\gamma$ rays have been converted to partial radiation widths and further analyzed to obtain average $E1\mathrm{}$ gamma strength. Individual $\gamma$ spectra from $I=3\mathrm{} \mathrm{and} 4$ resonances have been summed separately after appropriate normalizations. The resulting average radiation widths (and hence the $\gamma$-ray strength function) were in good agreement with the Axel-Brink predictions based on a giant dipole resonance model. These widths were also consistent with the assumption that the $\gamma$-ray strength function is independent of the initial spin. The partial $E1\mathrm{}$ radiation widths were subjected to a distribution analysis, revealing that these widths had a slightly narrower distribution than that predicted by the Porter-Thomas law. The ratio of the average population of a particular low-lying level from $I=4\mathrm{}$ resonances to its population from $I=3\mathrm{}$ resonances was found to be in good agreement with a five-step cascade model. The population of successive spins within a rotational band lay on smooth curves which, for different bands, were nearly parallel. A level scheme for ${}_{}{}^{168}{}_{}{}^{}\mathrm{Er}$ has been constructed, and the neutron separation energy for this nucleus was deduced as 7771.6±1.0 keV.

The $g$ factor of the 2972 keV isomer in ${}_{}{}^{130}{}_{}{}^{}\mathrm{Xe}$ was measured with the time-integral perturbed angular distribution method to be $g=-0.158\mathrm{}\pm 0.021$. The lifetime of this state was revised to be $T_{\frac{1}{2}}=5.17\mathrm{}\pm 0.11$ ns. These results determined the $\nu h_{\frac{11}{2}}^2$ configuration for the isomer, in agreement with the interacting boson approximation calculation including the fermion degrees of freedom.

The half-life of ${}_{}{}^{158}{}_{}{}^{}\mathrm{Tb}$ was determined to be 180 yr using a combination of isotope dilution mass spectrometry and radioactivity counting techniques. The total uncertainty in this value is 6%. Using the newly measured half-life for ${}_{}{}^{158}{}_{}{}^{}\mathrm{Tb}$, the cross section for the ${}_{}{}^{159}{}_{}{}^{}\mathrm{Th}$(n,2n)${}_{}{}^{158}{}_{}{}^{}\mathrm{Th}$ reaction at 14.8 MeV was determined to be 1.93 b with an uncertainty of 7%.

The reaction ${}_{}{}^{80}{}_{}{}^{}\mathrm{Se}$(t,p)${}_{}{}^{82}{}_{}{}^{}\mathrm{Se}$ has been studied with a 15 MeV triton beam. Twenty-four energy levels in ${}_{}{}^{82}{}_{}{}^{}\mathrm{Se}$ have been identified up to approximately 5.0 MeV excitation, 12 of which were previously unreported. Angular distributions were measured and compared with distorted-wave Born approximation calculations in order to make $L$ (and hence $J^{\pi }$) assignments.

The structure of low lying levels in ${}_{}{}^{99}{}_{}{}^{}\mathrm{Rh}$ and ${}_{}{}^{101}{}_{}{}^{}\mathrm{Rh}$ has been investigated with the (p,$\mathrm{n}\gamma$) reaction employing $\gamma$-ray spectroscopy techniques. Many new levels in both nuclei are proposed on the basis of $\gamma -\gamma$ coincidence data. Spin assignments for several levels have been determined from excitation function and angular distribution data. The results are compared to previous work and to the available theoretical calculations.

At $E\left({}_{}{}^7{}_{}{}^{}\mathrm{Li}\right)=22.0\mathrm{}$ MeV, forward-angle angular distributions have been measured for 37 states (or groups of states) up to an excitation energy of 9.1 MeV, using a multiangle spectrograph and a gas target.

For the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^7{}_{}{}^{}\mathrm{Li}$,p)${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$ reaction previously observed deviations of cross sections from statistical ($2J+1$) dependence can be accounted for in a simple model of direct six-nucleon transfer.

The thermodynamics and critical exponents of nuclear matter near the critical point of a liquid-gas phase transition are studied. We then investigate fluctuations near the critical point. One effect of a finite number of nucleons, as in nuclear reactions, is to wash out the first-order phase transition for several MeV below the critical temperature. This is manifested in the fact that there is a finite probability for the system to exist in the metastable or unstable regions of infinite matter. The phenomenological droplet model is applied to a wide range of recent data on fragment yields in the range $6<A<\mathrm{}52\mathrm{}$, and good fits are obtained. Heavy ion reactions are consistent with droplet formation in a supersaturated vapor, with supersaturation ratios up to 3.25. Proton-nucleus reactions are consistent with droplet formation in a saturated vapor.

Excitation functions of the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{12}{}_{}{}^{}\mathrm{C},\alpha ){}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ reaction were measured at ${\theta }_{\mathrm{lab}}=7.5\mathrm{}°$ between $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=14-40\mathrm{}$ MeV and angular distributions were measured from $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=17.8\mathrm{} \mathrm{to} 20.6$ MeV. Summed yields reveal prominent intermediate structure resonances over the entire range which correlate well to resonances previously observed in elastic data. The resonances show enhanced decays to excited rotational bands in ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ with reduced widths comparable to those for the elastic channel and an order of magnitude greater than those for the ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ ground state band. A discussion is given of the resonances as shape-isomeric states in a shell model secondary minimum in ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$, and of the selective alpha decay as being transitions to states of related configuration in ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$.

The collective mass and potential, the quantum corrections, and the inertia parameters of the ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$+${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$→${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ system are evaluated by means of the quantized adiabatic time dependent Hartree-Fock theory in a three-dimensional coordinate and momentum lattice. The interaction used, consisting of a direct finite range Yukawa force and a density-dependent term, is fitted by static Hartree-Fock calculations (including center-of-mass corrections) to binding energies and elastic electron scattering form factors in the mass region of interest here. The result of the fit is a new interaction, still without exchange terms, which for light nuclei reproduces the binding energies, the diffraction radii, and the surface widths. The sub-barrier fusion cross section for ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$+${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$→${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ calculated with this force in quantized adiabatic time dependent Hartree-Fock theory is in excellent agreement with experimental data in contrast to calculations using other interactions. For the evaluation of the fusion cross section above the barrier classical trajectory calculations are performed using a suitable phenomenological friction force. This yields agreement with experimental data up to energies of 40 MeV above the barrier. The quantum corrections and the dependence of the mass parameter on the fragment distance are shown to have an important impact only below the barrier.

Deep inelastic collisions between "light" heavy ions are considered in a formalism containing diffractive, diffusive, and statistical aspects. A closed-form diffractive cross section is derived, with the deflection function being parametrized in a classically-motivated way. A statistical argument is used to demonstrate how the observed double differential cross section is built up from different diffractive contributions each with its own weight. The form of the weighting function is derived. The observed forward-peaked exponentially-decaying form of deep inelastic collision angular distributions is accounted for. The possibility of exciting a nonzero spin state is explicitly included, enabling the same formalism to be used to explain the spin polarization occurring in deep inelastic collisions. This quantity is much more sensitive than the angular distribution to the choice of deflection function parametrization. Reasonable fits to data are obtained with only one free parameter, apart from an overall normalization factor.