The total inclusive (p,$x\mathrm{n}$) charge exchange reaction cross section on bismuth from 62 to 800 MeV was measured using activation and radiochemical techniques. These data for products with as many as 14 neutrons removed from the coherent product display the simple $E^{-1\mathrm{}}$ dependence of the total cross section with incident projectile energy. The distribution of charge exchange products is discussed in terms of quasifree processes in (p,n) reactions. A model comparison between the data and an intranuclear cascade calculation was satisfactory as evidenced by reproducing the energy dependence, cross section magnitude, and mass yields for products up to 14 neutrons removed. Better agreement between the model and data were obtained with mean-free paths of nucleons in nuclear matter twice as long as the one derived from nucleon-nucleon scattering.

Excitation functions for inelastic scattering of ${\pi }^{-}$ from ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}$ to the $1^{+}$ state at 10.2 MeV have been measured at constant momentum transfer $q=73\mathrm{}$ MeV/c. The incident energy was varied between 116 and 180 MeV. An upper limit was measured for the ${\pi }^{+}$ cross section at 116 MeV. The data are not fitted by distorted-wave impulse approximation calculations at this $q$ where the differential cross section is predicted to have its maximum. The discrepancy between theory and experiment is similar to the disagreement observed for ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}(\pi ,{\pi }^{\prime }){}_{}{}^{12}{}_{}{}^{}\mathrm{C}(1^{+},15.1\mathrm{} \mathrm{MeV})$.

We discuss various characteristics of Coulomb dissociation at low and high bombarding energies by means of model calculations. Sub-Coulomb breakup (of the deuteron) is generally quite well understood in the distorted-wave Born approximation framework. However, problems remain, especially for low energies of the emerging protons. The experimentally observed deviation of (d,p) breakup yields for intermediate ($E_{\mathrm{d}}=56\mathrm{}$ MeV) energy deuterons from the $A^{\frac{1}{3}}$ dependence is tentatively explained in terms of the Coulomb dissociation mechanism. It is shown that the Weizsäcker-Williams and Alder-Winther methods to calculate relativistic $E1\mathrm{}$ excitation cross sections yield the same result.

Contributions of quasifree and nonquasifree reaction processes to ($\pi$,$\pi \mathrm{N}$) reactions have been investigated across the (3,3) resonance region. We demonstrate that the quantum mechanical interference between these two types of reaction processes significantly affects the calculated ${\pi }^{-}$- and ${\pi }^{+}$- induced cross sections, as well as their ratio. In the case of incident ${\pi }^{-}$, the contributions from the interference term even exceed those from the pure nonquasifree term. This investigation of the ($\pi$,$\pi \mathrm{N}$) reaction thus indicates that the interpretations given to the parameter introduced into various published semiclassical models, in which interference effects were ignored, are incorrect.

The ${}_{}{}^{36}{}_{}{}^{}\mathrm{S}(n,\gamma ){}_{}{}^{37}{}_{}{}^{}\mathrm{S}$ reaction with thermal neutrons has been studied utilizing a highly enriched ${}_{}{}^{36}{}_{}{}^{}\mathrm{S}$ target. Fifteen $\gamma$ rays were observed which have been incorporated into a ${}_{}{}^{37}{}_{}{}^{}\mathrm{S}$ level scheme. The neutron separation energy of ${}_{}{}^{37}{}_{}{}^{}\mathrm{S}$ was determined to be 4303.52±0.12 keV; and the thermal neutron capture cross section of ${}_{}{}^{36}{}_{}{}^{}\mathrm{S}$ to be 230±20 mb. The subsequent ${\beta }^{-}$ decay of ${}_{}{}^{37}{}_{}{}^{}\mathrm{S}$ to levels in ${}_{}{}^{37}{}_{}{}^{}\mathrm{Cl}$ has also been studied. Seven $\gamma$ rays were observed which have led to an improved ${}_{}{}^{37}{}_{}{}^{}\mathrm{S}$ decay scheme.

The residues of the nucleon and $\Delta$ baryon poles in the baryonic current propagator are evaluated for the MIT and chiral bag models. It is found that the values obtained with a bag radius of 0.8 to 1 fm match those predicted by the quantum chromodynamic sum rules which take into account the chiral structure of the physical vacuum state. Smaller bag radii give increasingly poorer agreement.

Differential cross sections and analyzing powers have been measured between ${\theta }_{\mathrm{lab}}=6.5\mathrm{}° \mathrm{and} 34.5°$ for scattering of 547-MeV polarized protons from ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$. Data for the ${\mathrm{½}}^{-}$ (0.0), ${\mathrm{½}}^{+}$ (3.09), ${\frac{3}{2}}^{-} \mathrm{}\left(3.68\right)\mathrm{}$, ${\frac{5}{2}}_1^{+} \mathrm{}\left(3.85\right)\mathrm{}$, ${\frac{5}{2}}_2^{+} \mathrm{}\left(6.86\right)\mathrm{}$, ${\frac{5}{2}}^{-} \mathrm{}\left(7.55\right)\mathrm{}$, ${\mathrm{½}}_2^{-}$ (8.86), and ${\frac{9}{2}}^{+} \mathrm{}\left(9.50\right)\mathrm{}$ states are presented. The elastic scattering data were analyzed with a potential calculated in the impulse approximation and the resulting distorted waves were used in the distorted-wave impulse approximation analysis of the inelastic data with microscopic transition densities based on shell model wave functions.

800 MeV elastic $\overrightarrow{\mathrm{p}}+\mathrm{p}$ spin-depolarization and -rotation parameters $D_{\mathrm{NN}}$, $D_{\mathrm{SS}}$, $D_{\mathrm{LL}}$, $D_{\mathrm{SL}}$, and $D_{\mathrm{LS}}$ have been measured for the center-of-momentum angular range 4.8°-23.8° ($0.26 {\mathrm{fm}}^{-1\mathrm{}}\le q\le 1.28 {\mathrm{fm}}^{-1\mathrm{}}$). Statistical uncertainties are ≃±0.01-0.02 and total systematic uncertainty is ≤±0.035. The data are in overall agreement with predictions from global phase shift analysis.

The Bethe-Salpeter equation for NN-$\mathrm{N}\Delta$ scattering is extended to include $\Delta \Delta$ states also. With the exception of ${}_{}{}^1{}_{}{}^{}S_0^{}{}_{}{}^{}$, the effects are small for $T=1\mathrm{}$ because of dominance by $\mathrm{N}\Delta$ isobaric states. For $T=0\mathrm{}$ the influence is accordingly larger. Also a quasipotential approximation to the Bethe-Salpeter equation is considered. Substantial differences are found. In particular, the quasipotential results are considerably more sensitive to the coupling parameters of the transition interaction. As a result a better fit to existing experimental phase shift parameters is obtained with the Bethe-Salpeter equation.

The nucleon-nucleon polarization data around 2 GeV/c have a simple physical explanation. At and above this energy the nucleon-nucleon scattering is mainly "diffractive." The center-of-mass momentum is $p\sim m_{\omega }=780\mathrm{}$ MeV at this energy and the repulsive $\omega$-meson exchange with its strong $\mathrm{LS}$ force is dominant. At small nucleon-nucleon distances the nucleon sizes provide a natural damping of the meson exchange force at short distances.

A model is presented for the scattering of obliquely incident relativistic pions from a region of uniform nuclear matter. A simple analytic method that incorporates a second order optical potential in the Klein-Gordon equation is constructed. This method gives only one physically acceptable solution for which the real and imaginary parts of the wave number, $k$, inside nuclear matter are positive for all possible values of incident pion wave numbers, $k_0$. Reflectivity of pions indicates that the nuclear surface has higher transmission around $T_{\pi }\simeq 35$ MeV than at other energies, since the index of refraction of nuclear matter is near to unity there. The pion mean free path as a function of pion energy is plotted and discussed.

We present a method for parametrizing the 2×2 $S$ matrix for coupled-partial-wave nucleon-nucleon elastic scattering above the pion-production threshold; the prescription is to introduce two dummy absorptive channels and then to parametrize the consequent 4×4 $S$ matrix so that it is unitary and symmetric. The elastic but nonunitary 2×2 NN $S$ matrix is then recovered as a submatrix of the 4×4 matrix. We parametrize the 4×4 $S$ matrix by generalizing the prescription of Stapp, Ypsilantis, and Metropolis. The six real parameters that appear in the nonunitary NN sub $S$ matrix are well behaved as the interaction vanishes. Three of them parametrize absorption and appear in a real, symmetric 2×2 matrix $\mathit{N}$ which plays a role analogous to the absorption parameter $\eta$ for uncoupled waves. When there is no absorption, $\mathit{N}=1_{2\times 2}$ and the 2×2 NN $S$ matrix reverts to the standard Stapp-Ypsilantis-Metropolis form. We use a different set of 4×4 matrices to parametrize absorption than was used in the first paper in this series, with the result that the four sets of parameters that reproduce a given $S$ matrix are related by simple sign changes. The problem of the nontrivially related double solutions of the first paper is thus avoided.

We reconsider the $\frac{N}{D}$ equations for the $s$-wave spin-doublet trinucleon system and provide an alternative analytic model solution to these equations, which clearly explains most of the low energy properties of this system. The present model solution, is simpler than the previous approximate solutions proposed by other authors, and it provides a better understanding of the various lowenergy correlations for this system including the linear correlation between trinucleon energies and the neutron-deuteron scattering length.

Lorentz vector and scalar, isovector and isoscalar proton-nucleus optical potentials are obtained from invariant nucleon-nucleon amplitudes using a relativistic impulse approximation. Cross sections, analyzing powers, and spin rotation functions for ${}_{}{}^{90}{}_{}{}^{}\mathrm{Zr}$(p,p) and the ${}_{}{}^{90}{}_{}{}^{}\mathrm{Zr}$(p,n)${}_{}{}^{90}{}_{}{}^{}\mathrm{Nb}$ (isobaric analog state) reaction at 160 and 500 MeV are calculated using a relativistic generalization of the Lane equations. These predictions are compared to nonrelativistic impulse approximation results and to experimental data at 160 MeV.

We have calculated the ratio of the rate for nonmesonic decay of the $\Lambda$ in nuclear matter to that of the free $\Lambda$ decay rate using a pion and rho meson exchange model. Including tensor force effects and a final-state correlation function generated from the Reid-soft-core potential, we estimate $\frac{{\Gamma }_{\mathrm{nm}}}{{\Gamma }_{\mathrm{free}}}$ to be of order 1. A discrepancy with respect to the prior estimate of Adams is resolved.

We compute ${\pi }^{-}$ ground state energy levels in the Coulomb field of nuclei as a function of the external charge $Z$, taking into account the pion electromagnetic form factor in the Klein-Gordon equation. We compare our results to those obtained by solving the Klein-Gordon equation without the form factor or by solving an approximate Klein-Gordon equation from which virtual pair terms have been removed. We find the approximate Klein-Gordon equation to be a priori a better approximation to the form factor Klein-Gordon equation for an external point Coulomb field. In contrast, the Klein-Gordon equation turns out to be an excellent approximation to the form factor Klein-Gordon equation for physical (finite size) nuclei, unlike the approximate Klein-Gordon equation.

The Fermi-hypernetted-chain method for quantum many-body calculations is studied and investigated in some detail by calculations of the ground-state energy for neutron matter. The calculations are done for five different two-body potentials and results are compared with other theoretical results. Our Fermi-hypernetted-chain results are rather close to results obtained by lowest-order constrained variation calculations, and the results are quite dependent on the chosen potential, especially at high densities.

Using a two-body separable $t$ matrix between pairs, we solve the resulting four-body equations for four spinless bosons in the form that the 2+2 subsystem contribution is treated exactly by the convolution method. The 3+1 subamplitudes are represented as finite rank operators. We compare the utility of these methods both in four-body bound state and scattering calculations. We also develop an approximation that neglects four-body intermediate states in the 2+2 subsystem contribution and compare it with exact results. Finally, we present the results for a four-nucleon calculation with spin dependent $s$-wave separable interactions between pairs. These formally exact four-body equations are subsequently used to develop one parameter models to describe low energy phase shifts and cross sections for the reactions n ${}_{}{}^3{}_{}{}^{}\mathrm{H}$→n ${}_{}{}^3{}_{}{}^{}\mathrm{H}$, dd→dd, and dd→p ${}_{}{}^3{}_{}{}^{}\mathrm{H}$.

Monopole and quadrupole charge distributions of ${}_{}{}^{176}{}_{}{}^{}\mathrm{Hf}$, ${}_{}{}^{177}{}_{}{}^{}\mathrm{Hf}$, ${}_{}{}^{178}{}_{}{}^{}\mathrm{Hf}$, ${}_{}{}^{179}{}_{}{}^{}\mathrm{Hf}$, and ${}_{}{}^{180}{}_{}{}^{}\mathrm{Hf}$ were investigated by muonic atom $K$ and $L$ x-ray measurements. The model-independent Barrett charge radii $R_k$ and the isotope shifts $\Delta R_k$ were measured, and values of $〈r^2〉$ and $\Delta 〈r^2〉$ were deduced. A weak odd-even staggering of the nuclear charge radii was observed for the series ${}_{}{}^{176-178}{}_{}{}^{}\mathrm{Hf}$ and ${}_{}{}^{178-180}{}_{}{}^{}\mathrm{Hf}$. A large negative isomer shift was observed in the $2^{+}$ state of the ${}_{}{}^{176}{}_{}{}^{}\mathrm{Hf}$ nucleus, a fact that existing theories do not explain. The quadrupole moments of the first excited states of the hafnium nuclei were determined to be $Q^{176}\left(2^{+}\right)=-2.10\mathrm{}\left(2\right)\mathrm{} e$ b, $Q^{177}\left({\frac{9}{2}}^{-}\right)=1.30\mathrm{}\left(2\right)\mathrm{} e$ b, $Q^{178}\left(2^{+}\right)=-2.02\mathrm{}\left(2\right)\mathrm{} e$ b, $Q^{179}\left({\frac{11}{2}}^{+}\right)=1.88\mathrm{}\left(3\right)\mathrm{} e$ b, and $Q^{180}\left(2^{+}\right)=-2.00\mathrm{}\left(2\right)\mathrm{} e$ b. These quadrupole moments and the simultaneously determined $B\left(E2\right)$ values for the respective nuclei are in satisfactory agreement with the predictions of the axially symmetric rotor model.

The combined effect of the one pion exchange potential, the spin isospin dependent short range interaction, and the deformation on the $M2\mathrm{}$ states in light deformed nuclei is studied in the framework of a semiclassical model which describes these magnetic states as longitudinal (along the symmetry axis) and transverse spin isospin oscillations. It is argued that these states might present quite distinctive properties depending on the shape of the nuclei and on the strength of the short range repulsive interaction, due to the anisotropic character of the one pion exchange potential, which gives most attraction to the longitudinal mode in oblate nuclei only.