The total nuclear reaction probabilities for 4–13 MeV deuterons and 5–18 MeV ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ ions stopping in Si were measured, in coincidence studies of d${+}^3$He elastic scattering. These probabilities are about 3×${10}^{\mathrm{-}3}$ and 8×${10}^{\mathrm{-}4}$, respectively, for the most energetic d and ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ investigated, and are slightly lower than those predicted using total reaction cross sections ${\sigma }_R$ calculated with the optical model. Evidence of the DeVries-Peng scaling anomaly (deuterons have larger radii but smaller ${\sigma }_R$ than ${}_{}{}^3{}_{}{}^{}\mathrm{He}$) is presented.

Low-lying states of ${}_{}{}^{200}{}_{}{}^{}\mathrm{Pt}$ have been studied by the ${}_{}{}^{198}{}_{}{}^{}\mathrm{Pt}$(t,pγ) and (t,${\mathrm{pe}}^{\mathrm{-}}$) reactions with 16-MeV tritons. From detailed p-γ, p-${\mathrm{e}}^{\mathrm{-}}$, and p-γ-γ coincidence measurements, a level scheme that includes 16 excited states has been established. A 14.3-ns isomer is observed and is believed to correspond to the $7^{\mathrm{-}}$ isomers prevalent in the lighter even-mass platinum nuclei. Limited comparisons are made with the U(5) and O(6) symmetries of the interacting boson model.

Pion correlations are calculated for a recently proposed model of ultrarelativistic heavy-ion collisions. Ingredients of the model are evaporation of globs of quark-gluon plasma followed by pion scattering in the final state. The model predicts strong correlations between the longitudinal momentum and position of the source. The predicted transverse source size is smaller than preliminary findings from a recent experiment.

Mass number, atomic number, energy, and angular distributions were measured for the projectile-like fragments from the reaction ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$${+}^{40}$Ca at $E_{\mathrm{lab}}$=340 MeV. General features of this reaction are compared to other mass asymmetric systems. Considerable attention is given to the effect of the strong static driving force of the liquid drop (with shell and proximity corrections) potential energy surface on the first and second moments of the observed charge and mass distributions, as well as on associated correlations in the measured two-dimensional probability distribution P(A,Z). Comparison with an appropriate nucleon exchange transport model is made and discrepancies are discussed.

Alpha energy spectra and angular distribution have been measured for the reaction 120 MeV ${}_{}{}^{30}{}_{}{}^{}\mathrm{Si}$${+}^{30}$Si and compared to statistical model calculations. Emission from spherical nuclei cannot account for the shapes of the measured spectra. Reductions are required in both emission barrier and entrance channel spin. A simulation of alpha evaporation from deformed nuclei has been carried out using an equivalent one-step code. Average values of mass, charge, spin, and excitation energy of the emitter were evaluated by a multistep evaporative code. The very large deformation required to reproduce the experimental data agrees with previous results which have suggested a need for new physics in statistical models.

Two rotational band structures have been identified in doubly odd ${}_{}{}^{130}{}_{}{}^{}\mathrm{Pr}$ following the ${}_{}{}^{110}{}_{}{}^{}\mathrm{Cd}$${(}^{28}$Si,αp3n${)}^{130}$Pr reaction. One band, having no signature splitting, is believed to be built on the near-prolate π$h_{11/2}$⊗ν$g_{7/2}$ configuration. A second band, with a small signature splitting, is built on the triaxial π$h_{11/2}$⊗ν$h_{11/2}$ configuration. Systematics of recent results for the doubly odd ${}_{}{}^{130}{}_{}{}^{}$,132,134Pr isotopes are presented.

The structure of ${}_{}{}^{99}{}_{}{}^{}\mathrm{Pd}$ has been investigated via the ${}_{}{}^{96}{}_{}{}^{}\mathrm{Ru}$(α,n) and ${}_{}{}^{96}{}_{}{}^{}\mathrm{Ru}$${(}^6$Li,p2n) reactions in an attempt to populate low- and high-spin levels of this nucleus. Excitation functions and angular distributions of deexcitation γ rays have been measured to determine the spins of the levels deduced in γ-γ coincidence measurements carried out at 18 MeV (α particles) and 38 MeV ${(}^6$Li particles), respectively. Several new excited levels are found in the present measurements and the results show that the level structure of ${}_{}{}^{99}{}_{}{}^{}\mathrm{Pd}$ bears a strong resemblance to that of the isotone ${}_{}{}^{97}{}_{}{}^{}\mathrm{Ru}$. It appears also that ${}_{}{}^{99}{}_{}{}^{}\mathrm{Pd}$ may fit nicely into the systematics evinced in the heavier odd-A Pd nuclei.

One-proton and one-neutron stripping reactions induced by a 480 MeV ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ beam bombarding a ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ target have been studied using a high resolution energy loss magnetic spectrometer. The reactions are governed by two selection rules which are naturally contained in the one-step exact finite range distorted wave Born approximation formalism. Relative intensities of the populated states are well reproduced by this formalism as well as the absolute values of the cross sections. Comparisons with the results of one-nucleon stripping reactions induced by a ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ beam on a ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ target at 793 MeV incident energy are also presented; in this latter case the absolute cross section values are not reproduced.

We have made detailed angular distribution measurements for the inelastic scattering channel ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$${(}^{12}$C${,}^{12}$C${)}^{12}$C(${\mathrm{O}}_2^{+}$) in the region of a known prominent structure at $E_{\mathrm{c}.\mathrm{m}.\mathrm{}=29.0\mathrm{}}$ MeV. Our analysis shows that the two partial waves l=16ħ and 18ħ contribute significantly to this structure. The width and centroid of the contribution from the dominant l value, 18ħ, are identical to those of a structure seen in the inelastic $2^{+}$ channel.

Photon production cross sections in intermediate energy heavy-ion reactions are calculated using detailed balance. The model gives substantial photon yields and reproduces qualitatively the experimental observations. A possible influence of the Δ-isobar degree of freedom on the high energy photon yield is pointed out.

A two-parameter liquid drop model has been proposed to describe the symmetric fission process by using generalized Cassinian ovals as the function family of nuclear surface shapes. The saddle-point shapes and other properties have been calculated over a wide range of the fissility parameter x and compared with those using other methods. The agreement is surprisingly good. With the aid of an adiabatic approximation, the scission-point configurations for 0.3<x<0.67 have been determined, and the mutual potential energies at the scission point were calculated and are consistent with the experimental data for the most probable value of the total fission-fragment kinetic energy. The simple model has been extended to asymmetric systems, and, therefore, can be used in dynamical calculations for nuclear systems with large deformation.

Angular distributions of the spin-correlation parameters $A_{\mathrm{sl}}$ and $A_{\mathrm{ll}}$ for the reaction pp→${\pi }^{+}$d have been measured at pion center-of-mass angles 40${\mathit{°}\mathit{\le }{\theta }_{\pi }^{+}}^{\mathrm{*}}$≤130° at incident energies of 500, 650, and 800 MeV. Additional measurements of $A_{\mathrm{ll}}$ were made at 600, 700, and 750 MeV. The results of the experiment are compared with the predictions of several unified coupled-channel calculations and partial-wave analyses. While the latest partial-wave analyses were found to fit the data reasonably well, all except one of the various model predictions not only do not fit the data well, but also tend to be in disagreement with each other. The data show no clear sign of a need for proposed dibaryon resonances.

Data on 800 MeV polarized proton scattering on ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ and ${}_{}{}^{26}{}_{}{}^{}\mathrm{Mg}$ are presented. Angular distributions and analyzing power data have been extracted from fits to 26 peaks in the spectra for ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ and 23 peaks in ${}_{}{}^{26}{}_{}{}^{}\mathrm{Mg}$. Although there are a variety of shapes for the angular distributions, the analyzing power data for all states are positive and similar in magnitude and seem to be consistent with a two-body operator for the excitation with a spin structure much like that for the free proton-nucleon system. Evidence for a level in ${}_{}{}^{26}{}_{}{}^{}\mathrm{Mg}$ at 8.03 MeV with J>4 is presented. Comparison between the observed angular distribution, coupled channels, and distorted wave Born approximation calculations, and the angular distributions of excited states in neighboring nuclei, support the assignment of $J^{\pi }$${=5\mathrm{}}^{\mathrm{-}}$ or $6^{+}$. Coupled channels calculations for the $0^{+}$, $2^{+}$, $4^{+}$,${\mathrm{and}6}^{+}$ members of the ground state rotational bands of ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ and ${}_{}{}^{26}{}_{}{}^{}\mathrm{Mg}$ are compared to the data. Deformation parameters from distorted wave Born approximation calculations are determined for most of the angular distributions.

Relativistic calculations of elastic electromagnetic form factors of the deuteron are presented for momentum transfers up to 8 ${\mathrm{GeV}}^2$. Standard nucleon-nucleon interactions are used to construct a unitary representation of the inhomogeneous Lorentz group on the two-nucleon Hilbert space. Deuteron wave functions represent eigenstates of the four-momentum operator. Existing parametrizations of measured single-nucleon form factors are used to construct a conserved covariant electromagnetic current operator. Deuteron form factors are computed in terms of matrix elements of the current operator and the deuteron wave functions. The results are compared to experiment. The size of relativistic effects, scaling behavior, sensitivity to the nucleon-nucleon interactions, and effects of the uncertainties in measured nucleon form factors are investigated.

The interpretation of the observed narrow Σ-hypernuclear states in terms of poles of the S matrix in the second quadrant of the complex wave-number plane is considered. The value obtained for the time delay originated by the corresponding optical potential reinforces such an interpretation.

The reaction ${\mathrm{K}}^{+}$d→${\mathrm{K}}^{+}$d has been calculated for incident kaon momenta up to 1.5 GeV/c, using the relativistic Faddeev equations. The effect of multiple scattering corrections and of higher ${\mathrm{K}}^{+}$N partial waves has been evaluated, and the sensitivity of the results to the deuteron wave function and to variations of the on- and off-shell behavior of the elementary ${\mathrm{K}}^{+}$N amplitude has been studied. Some implications of the results in connection with Glauber’s high-energy limit are also discussed.

Proton-nucleus quasielastic scattering cross sections and spin observables are calculated in a relativistic plane-wave impulse approximation for nuclei from ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ to ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ at energies of 300 to 800 MeV. Relativistic effects are incorporated by using Dirac spinors with enhanced lower components characterized by an effective mass from 0.8 to 0.9M. The analyzing power is found to decrease significantly from free NN values when relativistic spinors are used. This reduction is in good agreement with data. Little change in polarization transfer coefficients $D_{i\mathcal{’}j}$ is found at 500 MeV. However, predictions of enhanced $D_{s\mathcal{’}s}$ and $D_{l\mathcal{’}l}$ are made at lower energies. Calculations are also presented for (p,n) quasifree charge exchange reactions. Here the analyzing power is almost unchanged but large changes in cross section and polarization transfer coefficients are possible. These changes depend on how pion contributions to the NN amplitudes are treated. Suggestions for future theoretical and experimental work are made.

Proton-induced pion production to the continuum was investigated via the reactions ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$(p,${\pi }^{\mathrm{-}}$)X, ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$(p,${\pi }^{+}$)X, and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$(p→,${\pi }^{+}$)X at bombarding proton energies of 250, 354, and 489 MeV, in the kinematic region where the pion has nearly its maximum allowable kinetic energy. Results from the ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$(p→,${\pi }^{+}$)X reaction indicate that at small missing momenta the analyzing powers can be adequately described by a quasi-free p→p→d${\pi }^{+}$ process, but as the missing momentum is increased this description becomes less accurate. The energy dependence of the cross section for the inclusive (p,${\pi }^{+}$) reactions is very similar to that of previously published exclusive (p,${\pi }^{+}$) data from the same target nuclei. The double differential cross sections for the ${\pi }^{\mathrm{-}}$ data, however, exhibit an energy dependence different from that of the exclusive (p,${\pi }^{\mathrm{-}}$) reaction.

Angular distributions were measured for excitation of the $2_1^{+}$(1.98), $2_2^{+}$(3.92), and $2_3^{+}$(5.26) states of ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$ by ${\pi }^{+}$ and ${\pi }^{\mathrm{-}}$ scattering at $T_{\pi }$=164 MeV. The data have been compared with distorted-wave impulse-approximation calculations using transition densities from the collective model, from electron scattering, and from the coexistence model. The calculations using (e,e’) transition densities reproduce the shapes of the angular distributions very well and the magnitudes of the cross sections to within 15%. The collective-model transition densities fail to fit the data unless the radius is adjusted from the ground-state value.

The influence of collision centrality upon mean kinematic characteristics and spectra of participant protons d+C, α+C, and C+C interactions at 4.2 GeV/c per nucleon is analyzed. The net charge Q of secondary particles is used as a measure of collision centrality. An increase in 〈$p_T$〉 of participant protons with increasing Q is observed for all types of interactions analyzed. The net charge is also seen to affect the form of the rapidity spectra of participant protons in C-C interactions. The intranuclear cascade model cannot explain the dependence of these proton characteristics upon Q.