Motivated by recent high-resolution muonic x-ray and electron scattering experiments, the mean field approximation with a realistic effective interaction has been applied in the rare-earth and nickel regions. For rotational rare-earth nuclei, the approximation of a single axially symmetric deformed intrinsic state yields quantitative agreement with the experimental binding energies, deformations, elastic electron scattering, and inelastic electron scattering to $2^{+}$ states. Discrepancies in transitions to $4^{+}$ and $6^{+}$ states may indicate the limits of validity of the simple deformed intrinsic state approximation. The recent radius measurements in Fe, Ni, and Zn isotopes have made it possible to test the degree to which the systematics of polarization of the charge distributions of nonspherical nuclei may be understood through the mean-field approximation. Although certain significant qualitative features have been understood, it is shown that the deformations of nuclei in this region are insufficiently defined to validate approximation by a single intrinsic wave function.

NUCLEAR STRUCTURE ${}_{}{}^{148,150}{}_{}{}^{}\mathrm{Nd}$, ${}_{}{}^{152,154}{}_{}{}^{}\mathrm{Sm}$, ${}_{}{}^{156}{}_{}{}^{}\mathrm{Gd}$, ${}_{}{}^{166}{}_{}{}^{}\mathrm{Er}$, ${}_{}{}^{176}{}_{}{}^{}\mathrm{Yb}$, ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$, ${}_{}{}^{252}{}_{}{}^{}\mathrm{Cf}$, ${}_{}{}^{54,56,58}{}_{}{}^{}\mathrm{Fe}$, ${}_{}{}^{58,60,62,64}{}_{}{}^{}\mathrm{Ni}$, ${}_{}{}^{64,66,68,70}{}_{}{}^{}\mathrm{Zn}$. Density-dependent Hartree-Fock predictions of energies and densities, comparison with electron scattering and muonic x-ray experimental results.

A microscopic model for the description of the giant multipole resonances in light deformed nuclei and their excitation via ($p, \gamma$) reactions is proposed. A version of Feshbach's formalism of nuclear reactions is used for which the bound states of the target and compound systems are described as linear combinations of angular momentum projected deformed hole and particle-hole configurations, respectively. The theory is applied to study the giant multipole resonances in ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ as seen via ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}(p, \gamma ){}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ reactions. Results for both the transitions to the ground state as well as the first $2^{+}$ excited state of ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ are calculated and a number of approximations are tested. The 90° yields are found to be in good agreement with experiment. Gross features as well as intermediate structures of the experimental cross sections are reasonably well reproduced.

NUCLEAR STRUCTURE ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$, ${}_{}{}^{19}{}_{}{}^{}\mathrm{Ne}$, ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$; Calculated spectra and $E1\mathrm{}$ transitions. Angular momentum projected Hartree-Fock and Tamm-Dancoff methods.

NUCLEAR REACTIONS ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}(p, \gamma )$; radiative capture. Calculated cross sections to ground and first excited state.

Excited states in ${}_{}{}^{105}{}_{}{}^{}\mathrm{Pd}$ have been populated using the reaction ${}_{}{}^{96}{}_{}{}^{}\mathrm{Zr}({}_{}{}^{12}{}_{}{}^{}\mathrm{C}, 3n\gamma ){}_{}{}^{105}{}_{}{}^{}\mathrm{Pd}$. A new multiple-detector coincidence technique has resulted in greatly improved $\gamma -\gamma$ coincidence statistics. Aligned members of particlecore multiplets observed formed $\Delta I=2\mathrm{}$ bands built on $\frac{11}{2^{-}}$ and $\frac{7}{2^{+}}$ states. Many other nonaligned members of multiplets were observed as well. A $\Delta I=1\mathrm{}$ band built on the $\frac{5}{2^{+}}$ ground state was also observed which has no counterpart in lighter Pd nuclei. All of these states have been successfully described by a general rotational model which assumes that ${}_{}{}^{105}{}_{}{}^{}\mathrm{Pd}$ is a slightly deformed nucleus. The model includes a full treatment of Coriolis effects and a variable moment of inertia.

NUCLEAR STRUCTURE ${}_{}{}^{96}{}_{}{}^{}\mathrm{Zr}({}_{}{}^{12}{}_{}{}^{}\mathrm{C}, 3n\gamma )$, $E=45\mathrm{}$ MeV; measured $I_{\gamma }\left[E\right({}_{}{}^{12}{}_{}{}^{}\mathrm{C}\left)\right]$, $I_{\gamma }\left(\theta \right)$, $\gamma -\gamma$ coin, $\gamma -\gamma$-direct. corr., oriented nucl. ${}_{}{}^{105}{}_{}{}^{}\mathrm{Pd}$ deduced levels, $J$,$\pi$, $\gamma$ multipolarity. Compared with rotational model.

We evaluate the effective shell-model interaction ${\mathcal{V}}_{\mathrm{eff}}$ for the $\mathrm{sd}$ shell, through second order as a function of an energy shift between the valence and unoccupied oscillator states. The Brueckner reaction matrix $G$ for the Reid soft-core potential is obtained in a single-particle basis sothe Pauli operator is treated exactly. In terms of second order in $G$, intermediate-state sums and the dependence of energy denominators on passive particles and holes are both treated with care. Significant dependence on the intermediate-state spectrum is found for ${\mathcal{V}}_{\mathrm{eff}}$ in both the $T=0\mathrm{}$ and $T=1\mathrm{}$ components. An energy shift yielding a total gap of about 49 MeV is found to yield $A=18\mathrm{}$ two-particle spectra in reasonable agreement with experiment in view of the expected role of 4p-2h intruder states. On the other hand, a comparison of the matrix elements of ${\mathcal{V}}_{\mathrm{eff}}$ with those determined by Chung and Wildenthal from spectra of $A=18\mathrm{} \mathrm{to} 22$ nuclei indicates a preference for a total gap between 35 and 40 MeV. These empirically determined gaps may be compared with a total gap of about 30 MeV, motivated by a study of the self-consistent particle spectrum by Gambhir and McCarthy.

NUCLEAR STRUCTURE Effective interaction, theory; convergence of intermediate-state sums; $A=18\mathrm{}$ spectra; shell-model matrix elements in the $\mathrm{sd}$ shell; realistic microscopic shell-model interaction through second order in the reaction matrix.

Starting with the time-dependent Hartree-Fock equation in density matrix form, we investigate the macroscopic description of the dynamics of the nuclear fluid involving the spin and isospin degrees of freedom, in conjunction with the presence of only central exchange interactions. The time-dependent Hartree-Fock equation can be cast into a set of conservation laws of the classical type coupling spin and isospin densities. With simple zero-range interactions, we obtain the normal modes of density propagations and the corresponding speeds of sound waves. In addition to the normal sound waves in which the total density varies with space and time, there are the spin sound waves in which the difference of the spin-up and the spin-down densities varies with space and time, the isospin sound waves in which the difference of neutron and proton densities varies with space and time, and finally, the spin-isospin sound waves in which the difference of the "parallel" spin and isospin densities and the "antiparallel" spin and isospin densities varies with space and time. It is found that for a zero-range interaction whose density dependence is of the type $t_3(1+{\mathcal{P}}^B)\frac{n\delta ({\overrightarrow{\mathrm{r}}}_1-{\overrightarrow{\mathrm{r}}}_2)}{6}$, the speeds of spin sound $a_2$, isospin sound $a_3$ and spin-isospin sound $a_4$ satisfy ${a_2}^2+{a_3}^2=2\mathrm{}{a_4}^2$. With the parameters of Golin and Zamick and Vautherin and Brink, we have in addition $a_3>a_4>a_2$, the numerical values of $a_2$, $a_3$, and $a_4$ being in the range of 0.17 to 0.27c.

NUCLEAR STRUCTURE Dynamics of nuclear fluid, normal sound wave, spin sound wave, isospin sound wave, and spin-isospin sound wave. Time-dependent Hartree-Fock theory. Estimate speeds of different sound waves.

Recent observations by Cooper et al. of the charge distributions in ${}_{}{}^{166}{}_{}{}^{}\mathrm{Er}$ and ${}_{}{}^{176}{}_{}{}^{}\mathrm{Yb}$ bring to mind an old idea that the ground state of finite nuclear matter may exhibit spatially periodic mass-density and charge-density modulation. A feasible experiment employing a polarized ${}_{}{}^{165}{}_{}{}^{}\mathrm{Ho}$ target is proposed. A spatially periodic charge modulation could most easily be detected by Bragg scattering of high-energy electrons.

NUCLEAR STRUCTURE Charge distribution; collective instabilities; electron scattering.

A recent paper dealing with high-spin states in rapidly rotating nuclei is shown to be fundamentally erroneous. Among other things, the assumption that the pairing interaction remains invariant in a time-reversal unsymmetric basis precludes the physical effects with which the paper is concerned. An alternative approach is proposed.

NUCLEAR STRUCTURE High-spin states, pairing interaction, self-consistent cranking model.

The half-life and the $K$ conversion coefficient of the 66-keV $\gamma$ transition in ${}_{}{}^{127}{}_{}{}^{}\mathrm{Cs}$ are measured using delayed coincidence and $\gamma -\gamma$ coincidence techniques.

RADIOACTIVITY ${}_{}{}^{127}{}_{}{}^{}\mathrm{Ba}$ [${}_{}{}^{133}{}_{}{}^{}\mathrm{Cs}(p, 7n)$], measured $\gamma \gamma \mathrm{}\left(t\right)\mathrm{}$ ICC; deduced $\gamma$ multipolarity, hindrance factor.

The recently proposed nuclear fireball model is used to calculate the low-energy (≲ 10 MeV) bremsstrahlung from relativistic heavy ion collisions. For low-energy photons with wavelengths larger than nuclear dimensions and frequencies smaller than the inverse collision time the bremsstrahlung is nearly independent of details of the collision process. The number of photons produced per collision depends strongly on the impact parameter. Production cross sections are generally strongly peaked in the forward direction with a broad hump in the backward direction, and appear to be large enough to be seen experimentally.

NUCLEAR REACTIONS Relativistic heavy ions, calculated bremsstrahlung, $E\lesssim 10$ MeV.

A new isomeric level at 561 keV [$T_{\frac{1}{2}}=87\mathrm{}\left(2\right)\mathrm{}$ nsec] in ${}_{}{}^{72}{}_{}{}^{}\mathrm{As}$ has been excited by the reaction ${}_{}{}^{59}{}_{}{}^{}\mathrm{Co}({}_{}{}^{16}{}_{}{}^{}\mathrm{O}, 2pn){}_{}{}^{72}{}_{}{}^{}\mathrm{As}$ using pulsed beams of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$. The spin-precession of this level has been observed in cobalt, and also, after recoil implantation, in nickel. The $g$ factor is measured to be $g=+0.116\mathrm{}\left(2\right)\mathrm{}$, which yields +274(7) kG for $B_{\mathrm{hf}}\left(\mathrm{As}\mathit{Co}\right)$.

NUCLEAR REACTIONS Pulsed beam: ${}_{}{}^{59}{}_{}{}^{}\mathrm{Co}({}_{}{}^{16}{}_{}{}^{}\mathrm{O}, 2pn)$; observed isomeric level; measured $T_{\frac{1}{2}}$, spin-precession in Co, Ni; deduced $g$, $B_{\mathrm{hf}}$.

In-flight annihilation corrections are considered to the energy spectrum shape measurement of ${}_{}{}^{12}{}_{}{}^{}\mathrm{N}$. Owing to this correction the slope measured to be (-0.17 ± 0.06)%/MeV may extend to -0.35%/MeV. This is to be compared with a slope of (-0.52 ± 0.02)%/MeV predicted if conserved vector current is assumed.

RADIOACTIVITY ${}_{}{}^{12}{}_{}{}^{}\mathrm{N}$; correction to spectrum-shape measurements, implication on CVC.

$\gamma -\gamma$ angular correlations have been measured for two cascades in ${}_{}{}^{97}{}_{}{}^{}\mathrm{Tc}$ following the decay of 2.9-day ${}_{}{}^{97}{}_{}{}^{}\mathrm{Ru}$. Using an NaI-Ge(Li) detector combination, the measured angular correlation coefficients are: 569-216 keV: $A_{22}=0.299\mathrm{}\pm 0.007$, $A_{44}=0.018\mathrm{}\pm 0.010$; 460-325 keV: $A_{22}=0.137\mathrm{}\pm 0.017$, $A_{44}=-0.009\mathrm{}\pm 0.027$. These data have been analyzed to yield the $\frac{E2\mathrm{}}{M1\mathrm{}}$ mixing ratios $\delta \mathrm{}\left(569\right)=+0.128\mathrm{}\pm 0.014$ and $\delta \mathrm{}\left(460\right)=-\left({0.56}_{-0.31\mathrm{}}^{+0.43\mathrm{}}\right)$.

RADIOACTIVITY ${}_{}{}^{97}{}_{}{}^{}\mathrm{Ru}$ [from ${}_{}{}^{96}{}_{}{}^{}\mathrm{Ru}(n, \gamma )$]; measured $\gamma \gamma \left(\theta \right)$; deduced ${}_{}{}^{97}{}_{}{}^{}\mathrm{Tc}$ $\gamma$ mixing ratios.

The possibility of introducing systematic errors in ($p, n$) threshold determinations due to the neutron detector geometry is demonstrated by measurements and calculations.

NUCLEAR REACTIONS ($p, n$); ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$, measured; ${}_{}{}^{54}{}_{}{}^{}\mathrm{Fe}$, ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$, ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}$, ${}_{}{}^{65}{}_{}{}^{}\mathrm{Cu}$, ${}_{}{}^{70}{}_{}{}^{}\mathrm{Zn}$, ${}_{}{}^{75}{}_{}{}^{}\mathrm{As}$, calculated; ${\sigma }_{p,n}$ near thresholds.

The 2.79 MeV bandhead of the $K^{\pi }={\frac{1}{2}}^{-}$ rotational band in ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$ is found to resonate near ${\theta }_{\alpha }=0\mathrm{}°$ in the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{13}{}_{}{}^{}\mathrm{C}, \alpha ){}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$ reaction. The resonance is not observed with the projectile and target reversed at the same c.m. energy. Similar behavior has previously been observed for the ${\frac{3}{2}}^{-}$ and ${\frac{5}{2}}^{-}$ members of this band. Because the ${\frac{1}{2}}^{-}$ level is a member of a closely spaced doublet, $\alpha -\gamma$ coincidence measurements were necessary to observe the resonance.

NUCLEAR REACTIONS ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{13}{}_{}{}^{}\mathrm{C}, \alpha \gamma )$, ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}({}_{}{}^{12}{}_{}{}^{}\mathrm{C}, \alpha \gamma )$, $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=13.9-15\mathrm{}$ MeV; measured $\sigma \left(\theta \right)$, $\theta =0\mathrm{}°, 180°$; measured $\alpha -\gamma$ coincidences; studied resonant yields for different final states.

It is shown that the recoil momenta of isotopes produced by fragmentation of relativistic ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ projectiles can be understood from kinematics and a two-fragment approximation.

NUCLEAR REACTIONS Recoil momenta of fragments from relativistic ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ projectiles. Kinematics and two-fragment model. Linear dependence on interfragment binding energy and target independence.

Ternary and binary fission barriers and their relative WKB penetrability have been calculated for the isotopes $184\le N\le 228$ of element 126, considering both $Z=114\mathrm{}$ or $Z=126\mathrm{}$ as magic numbers. In all cases the predicted relative rates $\frac{{\Gamma }_T}{{\Gamma }_B}$ of ternary to binary low-energy fission events are substantially higher than those known for actinides. Thus their observation could serve as a test for the superheavy element 126.

RADIOACTIVITY, FISSION ${}_{}{}^{310,...,354}{}_{}{}^{}126$(sf); calculated binary and ternary barriers, predicted relative $T_{\frac{1}{2}}$.

Cross sections for the ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}({}_{}{}^3{}_{}{}^{}\mathrm{He}, {\alpha }_0){}_{}{}^{47}{}_{}{}^{}\mathrm{Ca}$ reaction have been measured. A comparative distorted-wave Born approximation analysis of this reaction and of the ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}(d, t_0){}_{}{}^{47}{}_{}{}^{}\mathrm{Ca}$ reaction provides a zero-range normalization constant for the ($\alpha$, ${}_{}{}^3{}_{}{}^{}\mathrm{He}$) reaction of $D^2=18\mathrm{}\times {10}^4$ Me${\mathrm{V}}^2$${\mathrm{fm}}^3$, which is based on the much better known normalization constant for the ($t, d$) reaction of $D^2=3.9\mathrm{}\times {10}^4$ Me${\mathrm{V}}^2$${\mathrm{fm}}^3$.

NUCLEAR REACTIONS ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}({}_{}{}^3{}_{}{}^{}\mathrm{He}, {\alpha }_0)$, $E=9-13\mathrm{}$ MeV. Measured $\sigma (E, \theta )$. DWBA analysis of these and of 18 MeV results. Comparison with ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}(d, t_0)$. Deduced normalization constant for ($\alpha$, ${}_{}{}^3{}_{}{}^{}\mathrm{He}$) reaction.

The first paper of this series reported on energy-dependent and energy-independent phase-shift analyses of proton-proton elastic scattering data between 1 and 500 MeV. The present paper extends the analysis to include neutron-proton elastic scattering data between 0 and 425 MeV. Although this analysis is similar to those of the Livermore series, it differs in a number of important respects. First, a charge-splitting prescription has been employed for the isovector phases which includes Coulomb barrier effects and takes into account the difference in the masses between charged and uncharged pions. Second, a $K$-matrix formalism has been used to impose the constraints of the deuteron pole and the peripheral interaction (one-pion-exchange contribution) on the energy-dependent representation. Third, the neutron-proton and proton-proton scattering data have been fitted simultaneously in the search. The energy-dependent solution obtained uses 46 phenomenological parameters to represent 2670 data, with ${\chi }^2=2815\mathrm{}$. A number of the neutron-proton phases have changed from the values obtained in Livermore $X$ at higher energies, but the low-energy behavior is largely unaltered. A notable exception is the mixing parameter ${\epsilon }_1$ which has been strongly affected by the deuteron pole. The proton-proton phases are changed very slightly from the paper I values as a result of the additional $n-p$ constraints upon the $I=1\mathrm{}$ phases. We feel that the net result of these alterations is a more compact and reliable representation of nucleon-nucleon scattering in the energy range considered.

NUCLEAR STRUCTURE Energy-dependent and energy-independent phase-shift combined analyses of 1-425 MeV $n-p$ and 1-500 MeV $p-p$ scattering data.

Recent comprehensive analyses of $n-p$ data near 50 and 325 MeV reveal a complex ${\chi }^2$ hypersurface with nonquadratic behavior at 50 MeV and multiple minima at 325 MeV. We present the "most reasonable" solutions at these energies and present graphically some of the complex ${\chi }^2$ structure which invalidates the conventional measure of error on the resultant phase parameters.

NUCLEAR REACTIONS $n+p$ phase-shift analyses, 50 and 325 MeV.