It is shown that the ${\left(\pi d_{\frac{3}{2}}\right)}^{-2\mathrm{}}{(\nu f_{\frac{7}{2}},\nu p_{\frac{3}{2}})}^n$ model previously used to interpret the data on the lighter argon nuclei can be used to understand the recently observed results in ${}_{18}{}^{}{}_{}{}^{43}\mathrm{Ar}_{25}^{}{}_{}{}^{}$ and ${}_{18}{}^{}{}_{}{}^{44}\mathrm{Ar}_{26}^{}{}_{}{}^{}$. The first excited state of ${}_{18}{}^{}{}_{}{}^{44}\mathrm{Ar}_{26}^{}{}_{}{}^{}$ is predicted to be a core-excited $0^{+}$ level arising from the configuration ${[{{\left(d_{\frac{3}{2}}\right)}^{-4\mathrm{}}}_{00}\times {{\left(f_{\frac{7}{2}}\right)}^8}_{04}]}_{J=0,T=4\mathrm{}}$.

[NUCLEAR STRUCTURE shell model, $d_{\frac{3}{2}}$ protons $f_{\frac{7}{2}}-p_{\frac{3}{2}}$ neutrons; ${}_{}{}^{43}{}_{}{}^{}\mathrm{Ar}$ calculated levels, $J$; ${}_{}{}^{43,44,45,46}{}_{}{}^{}\mathrm{Ar}$ calculated binding energies.]

The $K$-shell autoionization probability in the ${\beta }^{-}$ decay of ${}_{}{}^{114}{}_{}{}^{}\mathrm{In}$ has been measured using a curved-crystal spectrometer. A value of (5.4 ± 0.4) × ${10}^{-4\mathrm{}}$ was obtained for the number of $K$-shell vacancies per ${\beta }^{-}$ decay. This result is in excellent agreement with the theoretical value predicted by Law and Campbell, which is 5.42 × ${10}^{-4\mathrm{}}$.

[RADIOACTIVITY ${\beta }^{-}$ decay of ${}_{}{}^{114}{}_{}{}^{}\mathrm{In}$; measured $P_K$.]

It is shown that the energy expression as a cubic polynomial (CP) in spin $I$, in addition to giving an excellent fit to the excitation energies of the ground-band levels in all even-even nuclei, also reproduces a critical spin $I_c$ beyond which the squared rotational frequency ${\omega }^2$ decreases although the moment of inertia $\mathcal{g}$ keeps on increasing, thus resulting in back bending in $\mathcal{g}-{\omega }^2$ plots. This feature is predicted to appear not only in well-deformed nuclei but at quite low spins in nearly spherical nuclei as well. Further, the CP formula predicts the nuclear moment of inertia for the first $2^{+}$ state to be smaller than that for the ground state for most of the hard rotors; correspondence of this characteristic with the shrinkage deduced from muonic atom studies and Mössbauer experiments is discussed.

The ion-implantation—perturbed-angular-correlation technique (IMPACT) has been used to measured the $g$ factor of the 204-keV ${\frac{3}{2}}^{+}$ level in ${}_{}{}^{95}{}_{}{}^{}\mathrm{Mo}$ nuclei recoiled into ferromagnetic iron and cobalt hosts. The observed angular precessions were $\omega \tau \left(Fe \mathrm{Mo}\right)=0.32\mathrm{}\pm 0.05$ and $\omega \tau \left(Co \mathrm{Mo}\right)=0.18\mathrm{}\pm 0.03$. The available direct lifetime measurements for the 204-keV states and the NMR hyperfine field measurements for molybdenum solutes in iron and cobalt are used to obtain the gyromagnetic ratio $g\left(204\right)=-0.24\mathrm{}\pm 0.03$. The sign of the hyperfine field for molybdenum in iron host was found to be negative.

[NUCLEAR REACTIONS ${}_{}{}^{95}{}_{}{}^{}\mathrm{Mo}({}_{}{}^{16}{}_{}{}^{}\mathrm{O}, {}_{}{}^{16}{}_{}{}^{}\mathrm{O}_{}^{\prime }{}_{}{}^{}\gamma )$, $E=30\mathrm{}$ MeV; measured ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}\gamma$-coin, $\gamma \gamma (\theta ,H)$. NUCLEAR MOMENTS ${}_{}{}^{95}{}_{}{}^{}\mathrm{Mo}$; deduced $g$ for 204-keV level.]

An evaluation of the effect of exchange currents on the momentum-transfer dependence of the inelastic form factor for nuclear isovector excitations, such as the dipole and monopole vibration, is given. It is found that departures from the hydrodynamic model prediction become important at $q\gtrsim 1$ ${\mathrm{fm}}^{-1\mathrm{}}$.

The multichannel three-body model is applied to the ($n\alpha \alpha$) system to study the bound states of ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$. The $\alpha$ particle involved in this system is assumed to be a two-level particle to take care of its internal structure. The energies of the ground state [${\frac{3}{2}}^{-}$] and an excited state [${\mathrm{½}}^{+}$] are calculated to be -1.76 and +0.68 MeV, respectively.

[NUCLEAR STRUCTURE ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$; calculated levels. Multichannel three-body model.]

It is emphasized that the propagator-renormalized Brueckner-Hartree-Fock self-consistent field theory (RBHF) is an improvement over the unrenormalized Brueckner approximation plus rearrangement energy corrections for two main reasons: (i) through the renormalization of the off-diagonal matrix elements of the single-particle potential in a fixed basis the shape and size of the field are modified, leading to increased nuclear radii and improved density distributions which affect the expectation values of all observables; (ii) through the solution of coupled equations for the "true" occupation probabilities, occupancy-rearrangement effects are calculated self-consistently rather than merely to lowest order. For an accurate test of the RBHF approximation in light nuclei, center-of-mass (c.m.) corrections to the calculated properties are quite important. Two ways of making the c.m. corrections, discussed earlier, are applied and compared in calculations with the Reid soft-core and Hamada-Johnston interactions for ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$. The RBHF equations are solved by matrix diagonalization in the harmonic-oscillator basis. The well depth of the oscillator reference potential for virtual "particle" states is determined by requiring self-consistency, for the low-lying "particle" states, with an average off-energy-shell RBHF self-energy. The binding energies are in good agreement with experiment, as is the radius of ${}_{}{}^4{}_{}{}^{}\mathrm{He}$, while the radius of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ is about 8% too small. A careful comparison of separation energies with experiment is made; c.m. corrections, the effect of spuriosity (presence of excited c.m. components) in the $0s_{\frac{1}{2}}$ hole state in ${}_{}{}^{15}{}_{}{}^{}\mathrm{O}$ or ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$, and second- and third-order rearrangement energies calculated earlier, are included. Details of density distributions and electron elastic scattering form factors are given. The possible existence of a dip in the proton density at the center of the $\alpha$ particle is discussed. The need for higher dimensionality in the calculation of form factors and properties of unbound single-particle states is established.

[NUCLEAR STRUCTURE Renormalized Brueckner-Hartree-Fock method; c.m., rearrangement corrections. ${}_{}{}^4{}_{}{}^{}\mathrm{He}$, ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$; calculated binding, SP $E$'s, separation $E$'s, true occupation probabilities, $\rho$, $e$-scattering form factor.]

Recent results concerning the application of the centrifugal stretching and the variable-moment-of-inertia (VMI) models to the description of ground-state bands in near-harmonic nuclei are discussed. As an extension of previous work dealing with deformed nuclei, the solutions of the centrifugal-stretching model which apply to near-harmonic and closed-shell nuclei are obtained and compared with those of the VMI model. In both cases there is more than one solution which applies to these nuclei. The irregularities observed in a plot of energy ratios $\frac{E_I}{E_2}$ vs $\frac{E_4}{E_2}$ for $\frac{E_4}{E_2}\sim 2$ are not well reproduced by either description but the predictions of the VMI model appear to correspond to the maximum and minimum values found experimentally. In the Te isotopes the transition between these limits takes place in a smooth way as the number of neutrons increases. The data of magic nuclei are only accurately reproduced by the VMI model. The ratios $\frac{E_4}{E_2}$ for these nuclei are found to be correlated with the extra binding due to closed shells.

[NUCLEAR STRUCTURE Complete solutions centrifugal stretching model. Comparison with VMI model for closed and near-closed shell nuclei.]

We present a derivation of the zero-angle polarization transfer $K_y^y$ (0°) in charge exchange and inelastic scattering using direct-reaction theory with central and tensor spin-dependent forces. The energy dependence of the calculated polarization transfer is sensitive to the relative strengths of the spin-independent, central spin-spin, and tensor forces. Adjustment of the parameters of a purely central force cannot reproduce the calculated results for central-plus-tensor forces, giving rise to the hope that measurements of data of this type will allow one to distinguish between central spin-spin and tensor forces. Numerical results are presented for ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$, ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$, and ${}_{}{}^3{}_{}{}^{}\mathrm{H}\mathrm{}(p,n)\mathrm{}$ reactions.

[NUCLEAR REACTIONS DWBA derivation of 0° $P$ transfer; calculation of ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}\mathrm{}(p,n)\mathrm{}$, ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}\mathrm{}(p,n)\mathrm{}$ analogs $E=16-28\mathrm{}$ MeV; ${}_{}{}^3{}_{}{}^{}\mathrm{H}\mathrm{}(p,n)\mathrm{}$ comparison with experiment.]

States in ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ were populated using the ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}({}_{}{}^{16}{}_{}{}^{}\mathrm{O},\alpha )$ reaction. Excitation functions were measured in the energy range $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=15.4-17.7\mathrm{}$ MeV for 47 excited states in ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ from 0 to 14 MeV excitation. Angular distributions were measured at a bombarding energy of 46 MeV for a number of the excited states and were observed to be symmetrical around 90° (c.m.). Fluctuation analyses of the excitation functions were made, and the results indicated a statistical compound-nucleus process for the reaction mechanism. Hauser-Feshbach calculations gave good agreement with the data and provided strong evidence for proposed high-spin members of the ground-state rotational band, and the $K=0^{+}$, $T=0\mathrm{}$ band in ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$.

[NUCLEAR REACTIONS ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}({}_{}{}^{16}{}_{}{}^{}\mathrm{O},\alpha )$, $E_{160}=40\mathrm{} \mathrm{to} 46$ MeV, measured $\sigma \mathrm{}\left(E\right)\mathrm{}$ for ${\theta }_{\mathrm{lab}}=7^{\circ }$; $E_{{}_{}{}^{16}{}_{}{}^{}\mathrm{O}}=46\mathrm{}$ MeV, measured $\sigma \left(\theta \right)$; ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ deduced levels. Fluctuation analysis. Hauser-Feshbach calculations and suggested $J$ values. Enriched targets.]

The ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, {\alpha }_0){}_{}{}^{15}{}_{}{}^{}\mathrm{N}$ reaction has been studied in the incident-energy range of 7-17 MeV at laboratory angles of 5 and 172.5°. These data are compared with previously reported ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^7{}_{}{}^{}\mathrm{Li}, {\alpha }_0){}_{}{}^{15}{}_{}{}^{}\mathrm{N}$ data over the same energy range in the compound system ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$. Resonant structure is observed in both reactions at $\theta =5^{\circ }$ with correlated structure at 24.7, 27.3, and 28 MeV excitation in ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$. Interpretation of this structure in terms of the resonant-cluster transfer model of Carlson and Johnson is discussed.

[NUCLEAR REACTIONS ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, {\alpha }_0){}_{}{}^{15}{}_{}{}^{}\mathrm{N}$, $E=7-17\mathrm{}$ MeV; measured $\sigma \mathrm{}\left(E\right)\mathrm{}$; $\theta =5\mathrm{} \mathrm{and} {172.5}^{\circ }$.]

Generalized nuclidic mass relationships represent a link between mass equations and mass relationships. They are partial difference equations which can be used recursively. The quality of mass predictions, particularly for very neutron-rich or proton-rich nuclei, depends essentially on our knowledge of the effective neutron-proton interaction $I_{\mathrm{np}}$. The transverse and longitudinal mass relationships of Garvey and Kelson which are special cases contain small systematic errors due to the assumed independence of $I_{\mathrm{np}}$ on the neutron excess or the nucleon number. Information about the dependence of $I_{\mathrm{np}}$ on $T$ and $A$ has been extracted from the experimental masses by a variety of ${\chi }^2$ tests and was found in partial disagreement with macroscopic and microscopic theories. Several procedure have been devised to test theoretical expressions for $I_{\mathrm{np}}$ for their compatibility and consistency with the experimental masses.

[NUCLEAR STRUCTURE Derived generalized nuclidic mass relationships with solutions; consistency tests.]

Angular distributions of the analyzing power of the reaction ${}_{}{}^3{}_{}{}^{}\mathrm{H}(\overrightarrow{p},n){}_{}{}^3{}_{}{}^{}\mathrm{He}$ have been measured at proton energies of 6.00, 9.96, and 13.55 MeV. These data are compared with available neutron-polarization data for the same reaction on a point-by-point basis and by means of associated Legendre-polynomial coefficients. In contrast to the comparison below 4 MeV, no significant difference exists above 6 MeV between the two observables at the same energies and angles. The data are also compared with $R$-matrix calculations based on the parameter sets of Werntz and Meyerhof. The previously reported excitation function for the analyzing power at ${\theta }_{\mathrm{c}.\mathrm{m}.\mathrm{}}={45}^{\circ }$ from 1.5 to 12 MeV is further documented.

[NUCLEAR REACTIONS ${}_{}{}^3{}_{}{}^{}\mathrm{H}(\overrightarrow{p},n){}_{}{}^3{}_{}{}^{}\mathrm{He}$, $E=6.00, 9.96, \mathrm{and} 13.55$ MeV; measured analyzing power $A\left(\theta \right)$.]

A measurement of the ${}_{}{}^3{}_{}{}^{}\mathrm{He}(e,d){}_{}{}^1{}_{}{}^{}\mathrm{H}$ 90° differential cross section between 10 and 21 MeV was made. The ${}_{}{}^3{}_{}{}^{}\mathrm{He}(e,d){}_{}{}^1{}_{}{}^{}\mathrm{H}$ cross section was converted into a ${}_{}{}^3{}_{}{}^{}\mathrm{He}(\gamma ,d){}_{}{}^1{}_{}{}^{}\mathrm{H}$ cross section. The shape of the ${}_{}{}^3{}_{}{}^{}\mathrm{He}(\gamma ,d){}_{}{}^1{}_{}{}^{}\mathrm{H}$ cross section agrees with recent theoretical calculations. We find no evidence for the anomalies (structure) in the ${}_{}{}^3{}_{}{}^{}\mathrm{He}(\gamma ,d){}_{}{}^1{}_{}{}^{}\mathrm{H}$ 90° differential cross section at excitation energies of 14.5 and 19.5 MeV reported in two recent experiments.

[NUCLEAR REACTIONS ${}_{}{}^3{}_{}{}^{}\mathrm{He}(e,d)$, $E_{\gamma }=10-21\mathrm{}$ MeV; deduced $\sigma (E_{\gamma }, {90}^{\circ })$.]

We test the validity of the sudden-approximation theory of deuteron stripping of Butler, Hewitt, McKeller, and May (BHMM) by testing its predictions of final-state angular distributions and spectroscopic factors against those of an essentially soluble model of stripping reactions. This model has been constructed with an excitable nuclear core which therefore allows a calculation of the final-state spectroscopic factor to be made in advance. it is based on the solution of the Faddeev equation for multichannel separable $s$-wave two-body interactions between proton and neutron, proton and core, and neutron and core. There are two features which characterize BHMM; one is the sudden approximation and the other is use of intermediate neutron states of a special sort. Both these features give rise to difficulties.

In this paper we reanalyze the $\mathrm{np}$ scattering data at a few MeV; we confirm, as previously suggested by Hopkins and Breit, that the $\mathrm{np}$ interaction models all predict the angular distribution well. Any further angular-distribution measurements must be very precise to contribute further to our knowledge.

[NUCLEAR REACTIONS $\mathrm{np}$ scattering $E\approx 10$ MeV; calculated $\sigma \left(\theta \right)$, $P\left(\theta \right),{\sigma }_T$, correlated experiments.]

Measurements of four vector-to-tensor and six tensor-to-tensor polarization-transfer coefficients for the elastic scattering of polarized deuterons by ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ are reported. Data were obtained at the laboratory angle 30° for energies in the range 5-9 MeV.

[NUCLEAR REACTIONS ${}_{}{}^3{}_{}{}^{}\mathrm{He}\mathrm{}(d,d)\mathrm{}{}_{}{}^3{}_{}{}^{}\mathrm{He}$, $E_d=5-9\mathrm{}$ MeV, ${\theta }_{\mathrm{c}.\mathrm{m}.\mathrm{}}={49.6}^{\circ }$, measured 10 polarization-transfer coefficients.]

We have calculated single and double charge exchange of pions on ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$, ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$, and ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$. The results are in rough agreement with the currently available experimental results.

[NUCLEAR REACTIONS ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}({\pi }^{+},{\pi }^0)$, $E=180\mathrm{}$ MeV; calculated $\sigma \mathrm{}\left(E\right)\mathrm{}$; ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}({\pi }^{+},{\pi }^{-})$, $E=180\mathrm{}$ MeV; calculated $\sigma \mathrm{}\left(E\right)\mathrm{}$; ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}({\pi }^{+},{\pi }^0)$, $E=30-200\mathrm{}$ MeV; calculated $\sigma \mathrm{}\left(E\right)\mathrm{}$; ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}({\pi }^{+},{\pi }^0)$, $E=180\mathrm{}$ MeV; calculated $\sigma \left(\theta \right)$; ${}_{}{}^9{}_{}{}^{}\mathrm{Be}({\pi }^{+},{\pi }^0)$, $E=30-250\mathrm{}$ MeV; calculated $\sigma \mathrm{}\left(E\right)\mathrm{}$; ${}_{}{}^9{}_{}{}^{}\mathrm{Be}({\pi }^{+},{\pi }^{-})$, $E=30-250\mathrm{}$ MeV; calculated $\sigma \mathrm{}\left(E\right)\mathrm{}$ to $T=\frac{3}{2}$ final states; ${}_{}{}^9{}_{}{}^{}\mathrm{Be}({\pi }^{+},{\pi }^0)$, $E=175\mathrm{}$ MeV, calculated $\sigma \left(\theta \right)$ to ground and sum of final states; ${}_{}{}^9{}_{}{}^{}\mathrm{B}({\pi }^{+},{\pi }^{-})$, $E=175\mathrm{}$ MeV, calculated $\sigma \left(\theta \right)$ to $T=\frac{3}{2}$ final states; ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}({\pi }^{+},{\pi }^0)$, $E=20-250\mathrm{}$ MeV, calculated $\sigma \mathrm{}\left(E\right)\mathrm{}$ to ground and sum of final states.]

A formal discussion of the optical potential due to Foldy and Walecka is extended to include spin and isospin degrees of freedom and projectile relativistic kinematics. The formalism is applied to intermediate-energy pion-nucleus elastic scattering. Assuming an infinitely heavy nucleon mass, we obtain a fixed-scatterer separable-potential parametrization of the two-body pion-nucleon scattering data in the laboratory system. This effective two-body potential is used in a consistent manner as microscopic input in the many-body pion-nucleus elastic scattering problem. Using the approximations adopted by Foldy and Walecka, we obtain a pion-nucleus optical potential which is then applied to study pion elastic scattering from ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$, ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$, and ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$. Total cross-section and angular-distribution predictions for pion kinetic energies $\sim 70-280$ MeV are presented. Good agreement is obtained with the available experimental data on ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$.

[NUCLEAR REACTIONS ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$, ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$, ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$; calculated pion-nucleus elastic and total reaction $\sigma$, elastic $\sigma \left(\theta \right)$. Separable pion fixed-nucleon interaction. Extended Foldy-Walecka formalism.]