The Jastrow method is extended to the treatment of tensor forces by the incorporation of suitable state dependence into the two-body correlation operator. The one- and two-body parts of the energy expectation value developed in a factor-cluster (Van Kampen) expansion, are evaluated for nuclear matter. Numerical results are presented for three semirealistic hard-core potentials with differing mixtures of central and tensor components. These results point to the necessity for an examination of three-body cluster corrections to the energy expectation value.

Angular distributions for the ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}(p,p^{\prime }){}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ reaction leading to the $J^{\pi }=2^{-}$ state at 8.88 MeV and the doublet of states at 6.05 MeV ($0^{+}$) and 6.13 MeV ($3^{-}$) have been measured at 23.4, 24.5, 27.3, 30.1, 34.1, 36.8, 39.7, 43.1, and 46.1 MeV. In the distorted-wave approximation (DWA) with central forces, the transition to the unnatural-parity ($2^{-}$) state can occur only through the spin-dependent part $V_{10}=V_{\sigma }f\left(r\right)\mathrm{}{\overrightarrow{\sigma }}_i·{\overrightarrow{\sigma }}_p$ of the effective two-nucleon interaction. The experimental angular distributions were compared with DWA calculations assuming $f\left(r\right)\mathrm{}$ has a Yukawa shape with a range of 1.0 F. Normalization to the measured cross sections determined the strength $V_{\sigma }$, which was found to decrease rapidly from a magnitude of 53 MeV to about 23 MeV between $E_p=17.0\mathrm{}$ MeV and $E_p=30.1\mathrm{}$ MeV, and then to decrease slowly to about 16 MeV at $E_p=46.1\mathrm{}$ MeV. The shape of the experimental angular distributions for the inelastic scattering to the $2^{-}$ state are well represented by the DWA at the lower energies, but the agreement deteriorates as the energy increases. The forward peak in the higher-energy data occurs at larger angles than the DWA prediction. The cross section calculated using a pseudopotential derived from the impulse approximation is too small by a factor of about 4 at all energies. The possible contribution of other reaction mechanisms to the cross section for scattering to the $2^{-}$ state is discussed. An analysis of the transition to the 6.1- MeV doublet is used to estimate the strength $V_c$ of the spin-isospin-independent part $V_{00}$ of the effective two-nucleon interaction. The experimental angular distributions for the 6.1- MeV doublet were also compared with the predictions of the impulse approximation.

A theory of particle-hole relations among spectra, presented in Part I, is extended to include hole-hole (hh) spectra as well as the particle-particle (pp) and particle-hole (ph) cases previously treated. This theory, which incorporates configuration mixing into many-body effective interactions, goes beyond the simple shell-model particle-hole relations of Pandya, Goldstein, and Talmi. A new shell-model relation involving all three partners (the triptych: pp, ph, and hh) is derived. We apply the many-body theory and the triptych relation to the nuclei ${}_{}{}^{42}{}_{}{}^{}\mathrm{Sc}$, ${}_{}{}^{48}{}_{}{}^{}\mathrm{Sc}$, and ${}_{}{}^{54}{}_{}{}^{}\mathrm{Co}$, which are partners in the $f_{\frac{7}{2}}$ shell. We find that we can then relate the spectra of these three nuclei to considerably greater accuracy than do the standard shell-model relations.

The cross section for the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}(\overline{p},\overline{p}n){}_{}{}^{11}{}_{}{}^{}\mathrm{C}$ reaction measured at 1.73 GeV is 28.2 ± 3.6 mb, a value virtually identical with that of the corresponding proton-induced reaction (27.5 ± 0.6 mb). The ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({\pi }^{-},{\pi }^{-}n){}_{}{}^{11}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}({\pi }^{-},{\pi }^{-}n){}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ cross sections at 2.36 GeV are 19.4 ± 1.5 and 16.0 ± 2.0 mb, respectively. Each is about 25% lower than the corresponding reaction induced by 2.4-GeV protons. These results are discussed in terms of the free-particle cross sections.

A microscopic analysis of the inelastic scattering of 17.7-MeV protons from ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ has been carried out. The angular distributions of the states at 2.900 MeV ($J=1\mathrm{}$), 3.414 MeV ($J=3\mathrm{}$), and 3.773 MeV ($J=3\mathrm{}$) are best characterized by $L=2\mathrm{}$, $L=2+4\mathrm{}$, and $L=2\mathrm{}$ distorted-wave (DW) curves, respectively. These combinations of $J$ and $L$ values identify these as unnatural-parity states. The microscopic analysis used Hamada-Johnston and Gaussian realistic interactions, a mixed-configuration ground state, and pure configurations for the excited states. Exchange effects were considered in an approximate way. Comparison of the DW curves with the data indicates that the ($p_{\frac{3}{2}}{f}_{\frac{5}{2}}$) configuration is predominant in the 2.900-MeV state.

An optical-model analysis has been made of available $p+{}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ elastic scattering data using the 11-parameter automatic search code SEEK. The analysis includes differential-cross-section and polarization angular distributions at 34 energies in the range 10-180 MeV. The available $p+{}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ total-reaction-cross-section data are also used in the analysis. Emphasis has been placed on determining the energy dependence of the optical-model parameters. When the higher-energy data, i.e., the data for incident proton energies greater than 100 MeV, are excluded, a common geometry for the optical potentials can be defined, and consequently the energy dependence is given entirely by the behavior of the strength coefficients of the various potential terms. The energy dependence of the real central potential for ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ can be represented by $\frac{\mathrm{dV}}{\mathrm{dE}}\cong -0.30\mathrm{}$. The fits to the experimental angular distributions are of the same quality or slightly better than those obtained in previous analyses. For some energy regions difficulties exist in fitting the large-angle data. The rms radius for the real-central-potential term is nearly constant over the entire energy range 10-75 MeV. The mean and standard deviation from the mean of the rms radius for the real central potential are 4.06 and 0.12, respectively.

Results are presented for the elastic scattering of 30.3-MeV polarized protons from targets of ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$, ${}_{}{}^{56}{}_{}{}^{}\mathrm{Fe}$, and ${}_{}{}^{59}{}_{}{}^{}\mathrm{Co}$. The angular region from 20 to 165° is covered with an absolute accuracy in the polarization measurements of about 0.01. The data, together with corresponding differential-cross-section data reported elsewhere, are analyzed using the optical model in a manner similar to that used for corresponding data for ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$, ${}_{}{}^{120}{}_{}{}^{}\mathrm{Sn}$, and ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$. The present results confirm the trends with mass number found earlier, suggesting that present forms of the model are only satisfactory for large nuclei (${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$), and that for lighter systems modifications are needed.

Particle-$\gamma$ angular correlations using the reactions ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}({}_{}{}^7{}_{}{}^{}\mathrm{Li},t\gamma ){}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}({}_{}{}^6{}_{}{}^{}\mathrm{Li},d\gamma ){}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ have been measured. The populations of the various magnetic substates in the residual nucleus were extracted from the data. The results indicate the presence of other reaction mechanisms competing with direct transfer of an $\alpha$ particle.

The level structures of the odd-odd nuclei ${\mathrm{Ga}}^{70}$ and ${\mathrm{Ga}}^{72}$ have been investigated by means of the thermal-neutron-capture reactions ${\mathrm{Ga}}^{69,71}(n,\gamma ){\mathrm{Ga}}^{70,72}$. Capture $\gamma$-ray spectra from isotopically separated targets of ${\mathrm{Ga}}^{69,71}$ have been studied with Ge(Li) spectrometer systems between 4500 keV and the neutron binding energies, and, for the ${\mathrm{Ga}}^{71}$ target, between approximately 80 and 670 keV. The results of these investigations are compared with previous data, and good agreement is generally obtained. They have led to the construction of the decay scheme of low-lying states in ${\mathrm{Ga}}^{70,72}$ and to the determination of the neutron binding energies 7651 ± 1 keV for ${\mathrm{Ga}}^{70}$ and 6519 ± 1 keV for ${\mathrm{Ga}}^{72}$.

Mössbauer-effect experiments following Coulomb excitation with a 6.0-MeV beam of ${\mathrm{He}}^4$ ions were performed with tungsten nuclei in tungsten compounds. The first excited states of ${\mathrm{W}}^{182}$, ${\mathrm{W}}^{184}$, and ${\mathrm{W}}^{186}$ were investigated simultaneously at both 78°K and between 20 and 30°K. Three different compounds of tungsten were used as absorbers: W${\mathrm{O}}_3$, WC, and W${\mathrm{S}}_2$. All three yielded consistent results for the relative quadrupole moments for the three tungsten isotopes. These are: $Q_{22}^{182}:Q_{22}^{184}:Q_{22}^{186}=1:0.965\mathrm{}\pm 0.008:0.906\pm 0.018,$ and are in reasonable agreement with values of the relative quadrupole moments determined from $B\left(E2\mathrm{}\right)\mathrm{}$ measurements and previous Mössbauer-effect measurements. If the natural linewidth of ${\mathrm{W}}^{182}$ is 0.997 ± 0.010 mm/sec, then the corresponding natural linewidth of ${\mathrm{W}}^{184}$ and ${\mathrm{W}}^{186}$ previously reported by Mekshes and Hershkowitz are corrected to 0.95 ± 0.09 and 0.80 ± 0.06 mm/sec. A comparison of the measurements of resonant absorption following Coulomb excitation with those from $B\left(E2\mathrm{}\right)\mathrm{}$ experiments indicate that the rotational model is valid for the lowest-lying energy levels of the even-even tungsten nuclei.

The decay of ${}_{}{}^{205}{}_{}{}^{}\mathrm{Hg}$ to levels in ${}_{}{}^{205}{}_{}{}^{}\mathrm{T}1\mathrm{}$ was investigated using Ge(Li) and NaI(T1) $\gamma$ detectors. On the basis of energy, intensity, and coincidence measurements a new decay scheme is proposed. In addition to the first excited state at 203.7 ± 0.2 keV seen in earlier decay studies, levels at 619.3 ± 0.4, 1140.9 ± 0.6, 1218.7 ± 0.4, 1340.3 ± 0.6, and 1433.9 ± 0.5 keV were observed. Spin assignments and $log\mathrm{ft}$ values are assigned to all levels. Our level scheme is compared with the results of recent reaction studies and with the predictions of a model that considers coupling between single-proton-hole states and vibrations of the core.

Two components in the spontaneous-fission decay of ${}_{}{}^{237m}{}_{}{}^{}\mathrm{Pu}$ have been investigated. The half-lives of the two isomers are 82 ± 8 nsec and 1120 ± 80 nsec. The production ratio of the two components was determined for three different bombarding conditions: ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}$ + 24-MeV $\alpha$ particles, ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}$ + 27-MeV $\alpha$ particles, and ${}_{}{}^{237}{}_{}{}^{}\mathrm{Np}$ + 12.1-MeV deuterons. The dependence of the production ratio on angular momentum deposition for the various reactions shows that the two shape isomers differ in spin, with the short-lived component corresponding to the lower-spin state. The experimental isomer ratios are compared with statistical-model calculations. Assuming the validity of the statistical description of isomer population, and the absence of a significant $\gamma$-decay branch for the high-spin isomer, the deformation associated with shape isomerism can be deduced from isomer-spin information extracted from the present experiment and reference to the Nilsson diagram at large deformation. The deformation indicated is approximately $\epsilon =0.6\mathrm{}$, in good agreement with theoretical estimates.

The level scheme of ${\mathrm{Gd}}^{155}$ has been studied using high-resolution Ge(Li), Si(Li), and standard scintillation counters. The analysis of the experimental data for this nucleus is impeded by an ambiguity in the spin values of the majority of its excitated states. In the present work $\gamma -\gamma$ angular correlations in the decay of ${\mathrm{Tb}}^{155}$-${\mathrm{Gd}}^{155}$ were measured using a Ge(Li) detector in coincidence with NaI(T1) scintillation counter. The spins of some of the levels up to the 648.1-keV level have been confirmed from various cascades. The analysis of the various coincidence experiments leads to the proposal of levels in ${\mathrm{Gd}}^{155}$ at 60.0, 85.5, 105.3, 118.0, 146.0, 235, 266.6, 268.6, 286.8, 326.0, 367.7, 427.4, 451.3, 488.8, 559.9, 592.6, 615.5, and 648.1 keV. A consistent level scheme of ${\mathrm{Gd}}^{155}$ is proposed and the spin and parity assignments of the levels are discussed. The multipolarity of the different $\gamma$ rays including the percentage of mixing is reported.

The $\gamma -\gamma$ directional correlations of the 779-617-keV $\gamma$ cascade and 814-697-keV $\gamma$ cascade in ${}_{}{}^{144}{}_{}{}^{}\mathrm{Nd}$ following the decay of ${}_{}{}^{144}{}_{}{}^{}\mathrm{Pm}$ ($t_{\frac{1}{2}}=349\mathrm{}$ day) were measured using a 10.6-${\mathrm{cm}}^3$ Ge(Li) detector and a 3×3-in. NaI(Tl) detector in conjunction with a multichannel analyzer in the standard fast-coincidence configuration. The results obtained are consistent with most-probable spin assignments (with second choice in the parentheses) to the various levels as $2^{+}$ for 1510 keV, $4^{+}$ ($6^{+}$) for 1791 keV, 3 (5) for 2093 keV, $4^{+}$ for 2203 keV, and $5^{-}$ for the ground state of ${}_{}{}^{144}{}_{}{}^{}\mathrm{Pm}$. The possible value of the quadrupole content for the 779-keV $\gamma$ ray is found to be in the range 11 to 20% or 61 to 80%, while for the 814-keV $\gamma$ ray, the possible value of the quadrupole content is in the range 36 to 94%.

Experimental data on the properties of low-lying levels of the odd-mass cesium isotopes are investigated within the framework of the intermediate-coupling approach in the unified nuclear model. The calculations are performed by assuming that either the last odd proton having available to it several single-particle states, or the three-proton-hole state in the $1g_{\frac{7}{2}}$ subshell, which can undergo excitations, is coupled to the quadrupole vibrations of the surface of the appropriate doubly even core. Using reasonable values for the parameters involved, the calculated low-energy spectra of ${\mathrm{Cs}}^{131}$, ${\mathrm{Cs}}^{133}$, and ${\mathrm{Cs}}^{135}$ are in good agreement with experimental data. The wave functions obtained from our model are used to calculate the electromagnetic transition probabilities, lifetimes, and magnetic dipole and electric quadrupole moments for several of the low-lying levels in each of the nuclei considered. These, too, are found to be in substantial agreement with the available experimental data. The results of our calculations are also compared with other theoretical work available.

The energy dependence of the integral recoil properties and formation cross sections of a number of barium and strontium nuclides produced in the interaction of ${\mathrm{U}}^{238}$ with protons has been studied between 0.45 and 11.5 GeV. The ranges and forward-to-backward ratios ($\frac{F}{B}$) of the neutron-excessive products are nearly independent of energy, and the results indicate that these products are formed in binary fission following interactions with low deposition energies. The ranges of the neutron-deficient products are practically constant up to 1 GeV, decrease by nearly a factor of 2 between 1 and 5 GeV, and decrease very slightly thereafter. The $\frac{F}{B}$ values exhibit a pronounced peak in the vicinity of the midpoint of this interval. The results up to 1 GeV are consistent with binary fission. At this energy a different mechanism becomes noticeable and by 5 GeV this process predominates. Comparisons are made with the results expected for spallation, fission of a moderately light nucleus, and fragmentation. The latter is the only process which can account for the various experimental results. It is concluded that fragmentation is the main mechanism for the formation of neutron-deficient products lying in the "fission" region for incident energies above 5 GeV.

The cross section of heavy-ion reactions is studied in the framework of the statistical theory of nuclear reactions. An expression is obtained for the probability of production of different isotopes in heavy-ion collisions. A comparison with the experimental data obtained recently in Dubna is given.

$\frac{E2\mathrm{}}{M1\mathrm{}}$ mixing ratios of the 709-, 714-, and 723-keV transitions in ${\mathrm{Te}}^{124}$, the 754-keV transition in ${\mathrm{Te}}^{126}$, and the 491-keV transition in ${\mathrm{Xe}}^{126}$ were measured using the $\gamma -\gamma$ directional-correlation technique. In addition, the measurements on the 646-603-keV, 1691-603-keV, and 2091-603-keV $\gamma -\gamma$ cascades in ${\mathrm{Te}}^{124}$ are in agreement with pure $E2\mathrm{}$ character of the 1691- and 2091-keV transitions in ${\mathrm{Te}}^{124}$. Coaxial Ge(Li) and Na(Tl) scintillation detectors were used in different combinations depending on the energy resolution required for a particular measurement. The results for the mixing ratios are $\delta \mathrm{}\left(709\right)={+0.04\mathrm{}}_{-0.05\mathrm{}}^{+0.03\mathrm{}}$, $\delta \mathrm{}\left(714\right)=+0.98\mathrm{}\pm 0.19$, and $\delta \mathrm{}\left(723\right)=-3.4\mathrm{}\pm 0.1$ for the transitions in ${\mathrm{Te}}^{124}$; $\delta \mathrm{}\left(754\right)={-5.5\mathrm{}}_{-0.3\mathrm{}}^{+0.4\mathrm{}}$ for the $2^{{+}^{\prime }}\to 2^{+}$ transition in ${\mathrm{Te}}^{126}$; and $\delta \mathrm{}\left(491\right)={+27\mathrm{}}_{-9\mathrm{}}^{+30\mathrm{}}$ for the $2^{{+}^{\prime }}\to 2^{+}$ transition in ${\mathrm{Xe}}^{126}$. There is an indication that the mixing ratios for the $2^{{+}^{\prime }}\to 2^{+}$ transitions in even-even tellerium isotopes are negative and the mixing ratios of similar transitions in even-even Xe isotopes have positive values.

Using a nuclear explosion as a neutron source, measurements were made of the fission cross sections of ${}_{}{}^{244}{}_{}{}^{}\mathrm{Cm}$, ${}_{}{}^{245}{}_{}{}^{}\mathrm{Cm}$, ${}_{}{}^{246}{}_{}{}^{}\mathrm{Cm}$, and ${}_{}{}^{248}{}_{}{}^{}\mathrm{Cm}$ between 20 eV and 3 MeV. Radiative-capture cross sections were measured at the same time for a sample of mixed Cm isotopes, consisting primarily of ${}_{}{}^{244}{}_{}{}^{}\mathrm{Cm}$ and ${}_{}{}^{246}{}_{}{}^{}\mathrm{Cm}$. Resonance analysis was carried out for ${}_{}{}^{244}{}_{}{}^{}\mathrm{Cm}$ between 20 eV and 1 keV, for ${}_{}{}^{246}{}_{}{}^{}\mathrm{Cm}$ and ${}_{}{}^{248}{}_{}{}^{}\mathrm{Cm}$ between 20 and 400 eV, and for the odd isotopes between 20 and 60 eV. The results of the analysis show evidence of intermediate structure in the sub-barrier fission of ${}_{}{}^{244}{}_{}{}^{}\mathrm{Cm}$.

The nuclear structure of the odd-$A$ indium isotopes with masses 115, 117, 119, 121, and 123 has been studied using the proton pickup reaction Sn ($d$, ${}_{}{}^3{}_{}{}^{}\mathrm{He}$) In with a deuteron bombarding energy of 28.9 MeV. Seven or more levels have been observed in each isotope. Excitation energies have been measured and $l$ values and spectroscopic factors have been extracted from the measured angular distributions. Ground-state $Q$ values have been measured relative to that for ${}_{}{}^{116}{}_{}{}^{}\mathrm{Sn}$. The five ($d$, ${}_{}{}^3{}_{}{}^{}\mathrm{He}$) spectra are quite similar. The ground state and levels at approximately 0.3 and 0.6 MeV in each nucleus are excited by pickup of a proton from the $1g_{\frac{9}{2}}$, $2p_{\frac{1}{2}}$, and $2p_{\frac{3}{2}}$ orbitals, respectively. These three levels contain approximately 70% of the $g_{\frac{9}{2}}$ sum-rule strength, 75% of the $p_{\frac{1}{2}}$ strength, and 50% of the $p_{\frac{3}{2}}$ strength. There is evidence for additional $g_{\frac{9}{2}}$ strength in $l=4\mathrm{}$ transitions near 1.4 MeV in each isotope. The existence of these transitions can be explained by an admixture of the $g_{\frac{9}{2}}$ hole configuration with the ${\frac{9}{2}}^{+}$ member of the multiplet formed by coupling a $g_{\frac{9}{2}}$ hole to the collective $2^{+}$ state near 1.2 MeV in the tin core. Transitions to levels weakly excited near 1.0 MeV in ${}_{}{}^{115}{}_{}{}^{}\mathrm{In}$, ${}_{}{}^{117}{}_{}{}^{}\mathrm{In}$, and ${}_{}{}^{119}{}_{}{}^{}\mathrm{In}$ are best reproduced with $l=2\mathrm{}$ distorted-wave-approximation curves. If these levels are populated by a one-step $l=2\mathrm{}$ direct reaction, it indicates a nonclosure of the $Z=50\mathrm{}$ proton shell in the tin ground state. Surprisingly, no $l=3\mathrm{}$ transitions corresponding to pickup of protons from the $1f_{\frac{5}{2}}$ orbital were observed, even though most of the isotopes were studied up to 3.5-MeV excitation.