The inner bremsstrahlung spectrum associated with the nonunique first-forbidden β decay of ${}_{}{}^{147}{}_{}{}^{}\mathrm{Pm}$ was measured employing the magnetic deflection method with a 4.5×5.1 ${\mathrm{cm}}^2$ NaI(Tl) scintillation spectrometer in the energy region 30–200 keV. The contribution due to the 121 keV source gamma ray line was subtracted by normalizing its peak with that of the 122 keV ${}_{}{}^{57}{}_{}{}^{}\mathrm{Co}$ gamma ray pulse height distribution recorded in the same experimental setup. The raw spectrum was unfolded following Liden and Starfelt and compared with theoretical spectral distributions. The measured spectral distribution does not match any of the theories in any part of the investigated energy region.

Detailed descriptions are given of previously reported measurements of the longitudinal polarization ($P_L$) of positrons in the allowed and unique second forbidden weak decays of ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$. The measurements were performed relative to the allowed decay of ${}_{}{}^{68}{}_{}{}^{}\mathrm{Ga}$ by application of time-resolved spectroscopy of the n=1 hyperfine states of positronium formed in powder media. Assuming the theoretical value $P_L$${(\mathrm{}}^{68}$Ga)=β(0.999±0.001), the results are $P_L$${(\mathrm{}}^{22}$Na, $3^{+}$→$2^{+}$)=β(+1.003±0.011) and $P_L$${(\mathrm{}}^{22}$Na, $3^{+}$→$0^{+}$)=β(+1.00±0.05). The allowed decay result (combined with other ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ experimental data on the decay rate, the capture ratio, the spectral shape, the βγ directional correlation, and the weak magnetic form factor) yields a determination of the full weak form factor structure of the transition through second order in recoil. The experimental value for the capture ratio is currently considered to be anomalously low compared to theoretical estimates. Our polarization result is not, however, sufficiently accurate to definitively favor one or the other value. The forbidden decay result, together with model-dependent nuclear structure calculations, restricts the contribution of previously neglected higher-order corrections to the allowed decay to be less than ${10}^{\mathrm{-}8}$.

A particle-rotor model which incorporates the variable moment of inertia formalism is applied to the N=88 transitional nuclei, ${}_{}{}^{149}{}_{}{}^{}\mathrm{Pm}$, ${}_{}{}^{151}{}_{}{}^{}\mathrm{Eu}$, and ${}_{}{}^{153}{}_{}{}^{}\mathrm{Tb}$. The model with a few adjustable parameters gives a very good account of the ΔI=1, ‘‘normal’’ and ΔI=2 ‘‘decoupled’’ band-like structures observed in these nuclei. The calculated level structure, single-nucleon-transfer spectroscopic factors, electromagnetic transition strengths, and relative gamma-ray branching are compared with available experimental data and predictions of other theoretical calculations.

The interplay between pairing and shape deformations at finite temperatures is studied with reference to an exactly soluble SU(2)×SU(2) model which is able to suitably mock up both superconductivity and the effects of long-range residual forces. Thermodynamic and ground state phase transitions are studied, both in the thermodynamic limit and in the case of a finite number of particles. Several independent quasiparticle approximations are analyzed with reference to the corresponding exact results.

Symmetry-conserving higher-order terms for the interacting boson model are constructed. Their eigenvalues are explicitly derived within the SU(3) limit. The influence of these interaction terms on the theoretical energy spectrum of several nuclei is discussed. The classical limit of these operators is derived and interpreted.

Results of both Brueckner-Bethe and variational calculations for the binding energy of nuclear matter as a function of density are presented for several recent nucleon-nucleon potentials. A detailed comparison is made for the Argonne $v_{14}$ potential, the most realistic potential for which both methods have been used. The two methods agree reasonably well, with predicted saturation points of -17.8 MeV at 1.6 ${\mathrm{fm}}^{\mathrm{-}1}$ for the Brueckner-Bethe method, and -16.6 MeV at 1.7 ${\mathrm{fm}}^{\mathrm{-}1}$ for the variational method. The variational energies are 1–2 MeV above the Brueckner-Bethe energies for densities from 1.2 to 1.7 ${\mathrm{fm}}^{\mathrm{-}1}$. The results of Brueckner-Bethe calculations are also given for the Paris and Bonn potentials as well as results of variational calculations for the Urbana $v_{14}$ potential. These potentials all give similar binding energy curves, and all saturate matter at a density significantly above the empirical value.

Expressions for the matrix elements of the interaction between proton and neutron bosons have been obtained for the case of a surface delta interaction acting in ${\mathrm{n}}^2$${\mathrm{p}}^2$ configurations. Boson-boson interaction matrix elements involving only bosons of angular momenta 0 and K are particularly simple, being proportional to the particle-particle interaction energy for orbital angular momentum K. The results obtained with the boson model are very similar to those previously obtained by diagonalization of the four-particle energy matrices for selected configurations of degenerate orbits.

A systematic study of neutron-proton multiplets in ${}_{}{}^{106\mathrm{-}116}{}_{}{}^{}\mathrm{In}$ isotopes is presented. Energy levels, wave functions, and magnetic dipole and electric quadrupole moments are calculated within the framework of neutron-quasiparticle proton-hole multiplets coupled to quadrupole phonon excitations of the underlying core. The role played by the neutron-proton interaction and the collective quadrupole vibrations is discussed.

The interacting boson model is able to reproduce the elusive two-particle-transfer data in the actinides (uranium and thorium). The same calculation also reproduces well the energy systematics and the B(E2) data.

The total fusion cross section for ${}_{}{}^{32}{}_{}{}^{}$S${+\mathrm{}}^{12}$C has been measured over the center-of-mass energy range from 16 to 28 MeV. The data show structures having peak-to-valley variations of 5–10% of the total fusion yield.

Angular distributions for the transitions to the $1^{+}$ ground state and $3^{+}$ first excited state of ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$ for the ${}_{}{}^7{}_{}{}^{}\mathrm{Li}$(p,d) reaction have been obtained at 200 and 400 MeV. It has been shown that the ratio for the excitation of the $3^{+}$ states relative to the $1^{+}$ state can be accounted for at bombarding energies ranging from 16 to 800 MeV by the addition of a small amount of 1$f_{7/2}$ in the wave function for the transition to the $3^{+}$ state.

Differential cross sections for pion elastic scattering from ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$ at 180 MeV have been analyzed within the framework of diffraction theory. Using a phenomenological determination of the underlying pion dynamics, we deduce the ratios of ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$ to ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ neutron and proton densities at a radius of 4.7 fm. The results obtained show that ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$ has a neutron skin in excess of ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ and the reverse for the proton skin, in agreement with Hartree-Fock densities, as well as previous determinations from μ x-rays and alpha scattering experiments.

A new variational method is applied to the solution of the Schroedinger equation for interacting few-body systems. The results for three nucleons interacting via the spin-dependent Malfliet-Tjon potential and three alpha particles interacting via the Ali-Bodmer potential are presented and compared with Faddeev and ATMS results, respectively.

Haas et al. recently observed a strong entrance-channel dependence in the angular momentum content of compound nuclei produced in fusion reactions. We explain the origin of these effects and analyze the cases of ${}_{}{}^{16}{}_{}{}^{}$O${+\mathrm{}}^{144}$Nd, ${}_{}{}^{37}{}_{}{}^{}$Cl${+\mathrm{}}^{123}$Sb, ${}_{}{}^{64}{}_{}{}^{}$Ni${+\mathrm{}}^{96}$Zr, and ${}_{}{}^{80}{}_{}{}^{}$Se${+\mathrm{}}^{80}$Se presented by Haas et al.

Angular distributions for elastic scattering of antiprotons from nuclei are analyzed in terms of a fuzzy black disk model. Data from ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$, and ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ at incident antiproton energies of 47 and 180 MeV are analyzed. The obtained fits are qualitatively good concerning the slope and position of the extrema, but are too deep in the minima.

An optical nonlocal potential depending linearly on the energy is transformed into a phase-equivalent energy-independent potential which depends on the angular momentum via l(l+1). The transformation is exact, can be performed for a large class of nonlocal potentials, and can be interpreted in terms of physics. The relation between hard and structural core for phase-equivalent potentials is discussed.

Relying on the recently measured energy of the double isobaric analog resonance in the reaction ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$(${\pi }^{+}$,${\pi }^{\mathrm{-}}$)${}^{208}$ Po, the parameters of the isobaric multiplet mass equation in heavy nuclei are examined. The analysis points to the possibility that a sizable second (or higher) order Coulomb energy is present.