Cross sections for ν${+}^{13}$C reactions are calculated both for charged- and neutral-current reactions in order to estimate the efficiency of a ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ target as a solar neutrino detector. The relevant transition matrix elements are obtained using the semiphenomenological effective-operator approach for p-shell nuclei.

The Coulomb-modified Faddeev equations were solved in momentum space for different separable potential models at ${\mathit{E}}_{\mathrm{lab}}^{\mathit{p}}$=2.5 and 3.0 MeV. The best agreement with available experimental data of zero- and first-order spin polarization observables was achieved by employing a separable approximation of the Paris potential in the calculation. These results, together with predictions of second-order p-d polarizations, demonstrate the necessity of a correct treatment of three-body Coulomb corrections. Moreover, no indication of model sensitivity is found in our results. Three-nucleon phase shift parameters are given and the validity of a simple approximate two-body description of the three-body Coulomb corrections is discussed.

Inverse scattering theory is used to determine local, energy-independent, coordinate space nucleon-nucleon potentials. Inversions are made of phase shifts obtained by analyses of data and from meson exchange theory, in particular the Paris and the Bonn parametrizations. Half-off-shell T matrices are generated to compare the exact meson theoretical results with those of inversion, and it is found that phase equivalent interactions have essentially the same off-shell behavior for any physically significant range of momenta.

We have measured differential cross sections for the ${}_{}{}^2{}_{}{}^{}\mathrm{H}$(d,p${)}^3$H and ${}_{}{}^2{}_{}{}^{}\mathrm{H}$(d,n${)}^3$He reactions at 11 deuteron bombarding energies from 20 to 117 keV. The differential data are accurate to 2.0% (relative) over most of the energy range, with an additional scale error of 1.3%. Integrated cross sections are derived with total errors generally about 1.5%. The results are compared with other measurements and with an existing R-matrix analysis. We find a larger D-wave reaction amplitude than previously reported. Formulas for the cross sections and reactivities are given.

The bremsstrahlung emission cross section from ${}_{}{}^3{}_{}{}^{}\mathrm{He}$+α collisions has been calculated and is found to compare quite satisfactorily with the experimental result. To describe the scattering system, we use the single-channel resonating-group wave functions which reproduce the essential characteristics, especially in the energy region including the important ${}_{}{}^2{}_{}{}^{}$F resonances. The photon-emission operator used is translationally invariant and the center-of-mass motion is strictly eliminated from the transition amplitude. The multipole component of this amplitude is written in closed form without invoking the long-wavelength approximation. These formulas can be used immediately for bremsstrahlung emission and other electromagnetic transitions in other light nuclear systems.

Proton and alpha decay from the giant resonance region of ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ excited with a 129 MeV alpha particle beam has been measured in coincidence with inelastic alpha particles detected at 0°. The angular correlation data show the presence of decay from both E0 and E2 giant resonances. The E0 giant resonance decays primarily through the ${\mathrm{\alpha }}_0$, ${\mathrm{\alpha }}_1$, ${\mathit{p}}_0$, and ${\mathit{p}}_{1,2}$ channels with the branching ratios 18±6 %, 24±8 %, 23±9 %, and 18±8 %, respectively. Substantial direct decay is observed.

As a continuation of our 0–30 MeV analysis we present a multienergy phase shift analysis of all pp scattering data below ${\mathit{T}}_{\mathrm{lab}}$=350 MeV. In the description of all partial waves we take exactly into account the long-range potential consisting of the improved Coulomb potential (including the magnetic moment interaction), the vacuum polarization potential, and the tail of the one-pion-exchange potential. To describe the short-range interaction in the lower partial waves we use a P-matrix parametrization. The intermediate partial waves are treated either by optimal mapping techniques or by using the Nijmegen soft-core potential. The latter gives a better description of the data. The final data set comprises 1626 scattering observables. The best fit to this final data set results in ${\mathrm{\chi }}^2$/${\mathit{N}}_{\mathrm{df}}$=1.117, where ${\mathit{N}}_{\mathrm{df}}$=1576 is the number of degrees of freedom. The pp${\mathrm{\pi }}^0$ pseudovector coupling constant is determined to be ${\mathit{f}}_0^2$=(74.9±0.7)×${10}^{\mathrm{-}3}$. Single-energy phase shifts and errors are also given.

We examine in detail the suggestion of Iqbal et al. for calculating the class-four charge symmetry breaking amplitude in n-p scattering. By simplifying to a model problem, we show explicitly that the approximation scheme is unreliable if a phenomenological, effective nucleon-nucleon T matrix is used. Our results have wider implications for observables calculated in relativistic impulse approximation calculations. They reinforce the observation made in the literature that the procedure of fitting only positive energy matrix elements can lead to an NN interaction whose off-shell behavior is incorrect.

The parity-nonconserving nucleon-nucleon interaction studied in nuclear systems provides a unique window on ΔS=0 hadronic weak processes. To check the predictions concerning the interactions between weak hadronic currents, low-energy nuclear physics processes appear to be very suitable. Considering the nuclear reactions induced by polarized protons as low-energy nuclear processes, we derive expressions for the longitudinal and irregular transverse parity-nonconserving analyzing powers, when the reactions take place via parity mixed resonances. Applications for ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$(p→,p${)}^{13}$C, ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$(p→,p${)}^{15}$N, and ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$(p→,α${)}^{12}$C resonance reactions are done.

The ${}_{}{}^{45}{}_{}{}^{}\mathrm{Sc}$(p,n${)}^{45}$Ti reaction was studied at 135 MeV with a beam-swinger system. Neutron kinetic energies were measured by the time-of-flight technique, with neutron detectors located in three detector stations at 0°, 24°, and 45° with respect to the undeflected beam. Flight paths of 131.0, 131.1, and 81.3 m were used. The overall timing resolution was about 825 ps, providing energy resolutions of 320 keV in the first two stations and 520 keV in the third. The wide-angle spectra are dominated by a complex at ${\mathit{E}}_{\mathit{x}}$=4.3 MeV. The angular distribution for this complex is fitted well by a distorted-wave impulse approximation calculation for an assumed ${\mathit{J}}^{\mathrm{\pi }}$=17/$2^{\mathrm{-}}$,19/$2^{\mathrm{-}}$ (π${\mathit{f}}_{7/2}^2$,ν${\mathit{f}}_{7/2}^{\mathrm{-}1}$) doublet. The spectra and angular distribution are consistent with (p,${\mathrm{\pi }}^{\mathrm{-}}$) excitations of the same states and are in good agreement with a full 1f-2p shell-model calculation. The 17/$2^{\mathrm{-}}$,19/$2^{\mathrm{-}}$ strength predicted by distorted-wave impulse approximation calculations using these shell-model wave functions is in good agreement with the experimental measurements.

The ${}_{}{}^{54}{}_{}{}^{}\mathrm{Fe}$(p,n${)}^{54}$Co reaction was studied at 135 MeV by the time-of-flight technique. Neutrons were detected with an energy resolution of 245 keV in large-volume, mean-timed counters at a flight path of 125 m. The forward-angle spectra are dominated by the excitation of $1^{+}$ states with characteristic Δl=0 angular distributions peaked at 0°. The strengths of the $1^{+}$ excitations are interpreted as being equivalent to Gamow-Teller (GT) strengths excited in beta decay. This strength is observed to be highly fragmented; GT strength is identified in more than 30 states. The B(GT-) strength is obtained relative to the Fermi strength B(F) assumed to be concentrated in the $0^{+}$, isobaric-analog ground state. The total B(GT-) strength observed in discrete states, combined with the B(GT+) strength obtained from the (n,p) reaction, yields a lower limit of 48 percent of the 3(N-Z) sum rule. Inclusion of Δl=0 strength in the background and continuum above a quasifree scattering background increases this lower limit to 73 percent. If one considers the Δl=0 strength observed in the full background and continuum up to ${\mathit{E}}_{\mathit{x}}$=25 MeV, the entire sum rule may be satisfied. The observed distribution of GT strength is in good agreement with a truncated 1f-2p shell-model calculation.

Angular distributions of the differential cross section, analyzing power, spin-flip probability, and spin-flip asymmetry in the excitation of the first $2^{+}$ states in ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ti}$ and ${}_{}{}^{50}{}_{}{}^{}\mathrm{Ti}$ were measured at incident energies of 11 and 18 MeV using the (p,p’γ) coincidence technique with a polarized proton beam. The angular distributions show strong incident energy and target dependence. The results were analyzed in terms of a macroscopic coupled-channels method based on the vibrational model and of the microscopic distorted wave Born approximation based on shell-model wave functions and effective nucleon-nucleon interactions. The spin-flip asymmetry is quite sensitive to the spin-dependent part in the interaction that causes inelastic scattering.

Binary reaction products from reactions of a ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ beam at energies 5.4, 5.9, 6.7, and 7.5 MeV/nucleon with targets of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{26}{}_{}{}^{}\mathrm{Mg}$, ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$, ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$, ${}_{}{}^{35}{}_{}{}^{}\mathrm{Cl}$, ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$, ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}$, and ${}_{}{}^{\mathrm{nat}}{}_{}{}^{}\mathrm{Zn}$ have been measured with a kinematic coincidence method. The γ-ray multiplicities are measured at the same time with NaI detectors and presented as a function of fragment mass. The results indicate that all aligned and statistically excited spin modes of the fragments are fully populated in compound nucleus fission reactions. In quasifission reactions the relaxation processes seem to terminate before full statistical spin equilibrium is reached. The results are analyzed and discussed in terms of various dinuclear spin modes with different characteristic relaxation times. The influence of various terminal freeze-out shapes is also discussed.

Electromagnetic dissociation cross sections for one, two, and three nucleon removal were measured for an ${\mathit{E}}_{\mathrm{lab}}$/A=14.6 GeV ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ beam impinging on ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$, ${}_{}{}^{120}{}_{}{}^{}\mathrm{Sn}$, and ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ targets. The measured cross sections exhibit an approximate ${\mathit{Z}}_{\mathit{T}}^2$ dependence and are well reproduced by calculations convoluting the virtual photon spectrum with the experimental σ(γ,N) photonuclear cross sections. Comparison with other experimental results and energy dependence of the cross sections are discussed.

We present phenomenological and folding optical-model descriptions of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$${+}^{12}$C elastic scattering between 6 and 120 MeV/nucleon. The potentials have a deep real part, a weakly absorbing imaginary part, and are energy dependent. The folding-model real potential is calculated from the energy- and density-dependent effective interaction DDM3Y. It requires renormalizations of about 1.1 below 10 MeV/nucleon, and close to unity above. The phenomenological real potential is about 300 MeV at the center for the lower energies, slowly reducing to 120 MeV for the highest energies. The discrete ambiguities for the real part found in the analysis at energies below 10 MeV/nucleon are resolved by demanding consistency with the higher energy results. The volume integrals for the folding-model and phenomenological potentials agree and display a smooth and slow energy dependence that is consistent with simple dispersion-relation predictions. The values for the total reaction cross sections show the transparency effect expected from microscopic calculations. A possible extension of this description towards lower energies is discussed.

Angular correlations between γ rays and fission fragments were measured in the reaction ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$${+}^{181}$Ta at 105 and 141 MeV bombarding energy. These correlations are used to extract the probability of giant dipole resonance γ-ray emission relative to the spin axis of the compound system which gives direct information about the projection quantum numbers of the split giant dipole resonance components in a deformed nucleus. Large anisotropies observed in the γ-ray energy region of the compound nucleus giant dipole resonance demonstrate unambiguously a deformed shape of the ${}_{}{}^{200}{}_{}{}^{}\mathrm{Pb}$ compound system at excitation energies of 69.5 and 102.4 MeV. The singles and fission-coincidence γ-ray spectra are fitted consistently in terms of the statistical γ-ray decay of the compound system and excited fission fragments. The giant dipole resonance parameters of these fits are then used to compute the γ-ray angular distribution with respect to the compound nucleus spin axis for prolate and oblate shapes. At 69.5 MeV the γ-ray anisotropy relative to the compound nucleus spin axis is well described by a prolate shape with a deformation β=0.43 in general agreement with theoretical predictions of a superdeformed shape in ${}_{}{}^{200}{}_{}{}^{}\mathrm{Pb}$. However, the large observed deformation survives to much higher temperatures than predicted. At 102.4 MeV the data require a reduction of the fission probability in the very early decay steps of the compound system. At this excitation energy the extraction of the shape of the ${}_{}{}^{200}{}_{}{}^{}\mathrm{Pb}$ nucleus is ambiguous, allowing both a collective prolate as well as a noncollective oblate shape.

We investigate the generation of transverse momentum in high-energy heavy-ion collisions and its relation to the nuclear equation of state. We find that streamer chamber data can be fitted by Boltzmann-Uehling-Uhlenbeck calculations with a momentum-dependent potential that closely models realistic nuclear matter interactions and yields an equation of state with K=215 MeV.

Gamma-ray and conversion electron measurements have been performed in the reactions ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$${(}^{24}$Mg,2αp${)}^{73}$Br at 110 MeV and ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$${(}^{36}$Ar,3p${)}^{73}$Br at 130 MeV, respectively. From γγ coincidence data the previously known level scheme was confirmed and extended up to probable spin I=45/2. In the conversion electron spectra, the decay of the previously postulated 27 keV state was observed for the first time. From the measurement of internal conversion coefficients, multipolarities of seven transitions in the bandhead region of ${}_{}{}^{73}{}_{}{}^{}\mathrm{Br}$ were determined and allowed spin-parity assignments to be established. High spin properties and quasiparticle alignment effects are discussed in comparison with ${}_{}{}^{75}{}_{}{}^{}\mathrm{Br}$.

The reaction of ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$ with ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ has been studied at a bombarding energy of E/A=8 MeV. Fragments ranging from lithium to titanium isotopes were detected in charged-particle detectors placed at a small forward angle (θ=11°). The coincident gamma rays were observed also and used to determine the populations of various bound excited states. The products could be generally described as either complex fragments or evaporation residues. An analysis of fragment velocities and a limited number of charged-particle coincidence events suggests that the complex fragments are emitted in a binary-decay process from the compound nucleus. The extent of statistical equilibrium of the compound nucleus was studied by analyzing the population distributions of both the complex fragments and the evaporation residues. The deduced nuclear temperatures of the complex fragments were found to be in general agreement with that expected for the compound nucleus. The observed (relative) populations of states in a typical evaporation residue were compared with predictions of a statistical evaporation code. The good agreement achieved suggests that heavy fragments with masses close to the total mass in the reaction are produced from the compound nucleus by the statistical emission of light particles, such as nucleons and alpha particles. The populations of states in nuclei with A≤35, somewhat beyond the mass range of statistical evaporation, are consistent with thermal excitation, and these nuclei must be the reaction partners of the light complex fragments. Thus, all of the detected fragments are consistent with decay of an equilibrated compound nucleus by either sequential light-particle emission or binary decay into large complex fragments.

The level structure of the transitional even-even ${}_{}{}^{136}{}_{}{}^{}\mathrm{Ce}$ nucleus has been investigated using the ${}_{}{}^{122}{}_{}{}^{}\mathrm{Sn}$${(}^{18}$O, 4nγ) reaction. The prominent structure observed at high spin is a ΔI=1 rotational band, populated with ∼25% intensity of the $2^{+}$→$0^{+}$ transition, which has a low dynamic moment of inertia <20${\mathrm{ħ}}^2$ ${\mathrm{MeV}}^{\mathrm{-}1}$ for frequencies below ħω=0.45 MeV. This band is interpreted in terms of a two-quasiproton-two-quasineutron configuration with a shape close to the collectively rotating γ=-60° oblate shape, and is related to the oblate π${\mathit{h}}_{11/2}$⊗[ν${\mathit{h}}_{11/2}$${]}^2$ configuration seen in several nearby odd-Z nuclei. The systematics of such oblate rotational bands in this mass region are discussed. Other ΔI=2 bands, built on states including ${\mathit{h}}_{11/2}$ quasineutron orbitals, are also associated with collective oblate rotation. In addition, tentative evidence is presented for a weak band (<2% intensity), showing an enhanced dynamic moment of inertia ∼57${\mathrm{ħ}}^2$ ${\mathrm{MeV}}^{\mathrm{-}1}$, built on the highly deformed [ν${\mathit{i}}_{13/2}$${]}^2$ prolate configuration.