Earlier ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}\mathrm{}(t,p)\mathrm{}{}_{}{}^{16}{}_{}{}^{}\mathrm{N}$ data for levels between 5.5 and 8.5 MeV excitation have been subjected to a distorted-wave Born-approximation analysis in order to extract $L$ values and place limits on $J^{\pi }$. Three $1^{+}$ levels are located at 6422, 6512, and 7006 keV, and possibly at 5520 keV. Several levels are suggested to be unresolved doublets.

NUCLEAR REACTIONS DWBA analysis of ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}\mathrm{}(t,p)\mathrm{}$, $E\left(t\right)=12.0\mathrm{}$ MeV; ${}_{}{}^{16}{}_{}{}^{}\mathrm{N}$ levels deduced, $L$, $J^{\pi }$. $E_x=5.5\mathrm{}-8.5$ MeV.

Neutron-proton bremsstrahlung cross sections $\frac{d\sigma }{d{\Omega }_{p}d{\Omega }_n}$ and asymmetries at $E_{\mathrm{lab}}=200\mathrm{}$ MeV have been calculated using the Lomon-Feshbach and Hamada-Johnston models. The cross sections from these models differ by about 10% at ${\theta }_p={\theta }_n=30\mathrm{}°$ after approximate adjustments are made for elastic scattering differences. The cross sections integrated over only the larger peak in the ${\theta }_{\gamma }$ distribution differ by about 16%. The calculations are based on an expansion of the electromagnetic current in powers of the photon energy rather than an expansion of the complete bremsstrahlung matrix element. The calculation includes the external emission amplitude to all orders in the photon energy and the electric dipole part of the internal emission amplitude. Higher order contributions to the internal emission amplitude are discussed. The numerical results and amplitude expressions are compared with those of other authors. We find numerical agreement with Brown and Franklin but not with Celenza, Gibson, Liou, and Sobel.

NUCLEAR REACTIONS $\mathrm{NN}$ bremsstrahlung amplitudes, nonlocal and exchange effects; $\mathrm{np}$ bremsstrahlung $\frac{d\sigma }{d{\Omega }_{p}d{\Omega }_n}$ and asymmetry calculated at $E_{\mathrm{lab}}=200\mathrm{}$ MeV with Lomon-Feshbach and Hamada-Johnston models.

Angular distributions for the inelastic scattering of protons from ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ have been measured at a proton energy $E_p=40\mathrm{}$ MeV with a resolution of 16 keV. The results for the natural parity states in the excitation energy range from the ground state up to $E_x\approx 13.5$ MeV are presented. The data have been analyzed using a macroscopic collective model. Coupled-channel calculations assuming the rigid-rotor model have been performed for the ground-state rotational band in ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$. Previous conclusions on the smallness of the parameter of the hexadecapole deformation have been confirmed. The angular distribution for the $6^{+}$ member of the ground-state rotational band at 8.120 MeV made it possible to extract the sixth order deformation parameter. Negative values of ${\beta }_6$ are suggested by the data. Collective model distorted-wave Born approximation calculations were performed to determine the deformation parameters ${\beta }_L$ and isoscalar transition rates $B(\mathrm{IS},0_1^{+}\to L)$ for most of the observed states. Nearly half of the strength observed below $E_x=13.5\mathrm{}$ MeV for the transitions of multipolarities $L=2,3, \mathrm{and} 4$ is contained in the high-energy region between $E_x=7.5\mathrm{} \mathrm{and} 13.5$ MeV. Good agreement with the inelastic electron scattering data has been obtained for most of the low-energy transitions which were previously studied via ($e,e^{\prime }$). Evidence is presented in favor of a particular spin value for a number of states for which only multiple spin assignments were previously made.

NUCLEAR REACTIONS ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}(p,p^{\prime })$, $E=40\mathrm{}$ MeV; measured $\sigma (E_{p^{\prime }};\theta )$; deduced ${\beta }_L\text{'}\mathrm{s}$, optical parameters. Enriched target.

A new measurement of the reaction ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}\mathrm{}(d,t)\mathrm{}{}_{}{}^{17}{}_{}{}^{}\mathrm{O}$, and a distorted-wave Born-approximation analysis, yield spectroscopic factors of 1.48 and 0.29 for the ${\frac{5}{2}}^{+}$ ground state and ${\frac{1}{2}}^{+}$ first-excited state, respectively. The ratio 0.195±0.015 is still in serious disagreement with a recent theoretical value of 0.27. Inclusion of inelastic two-step processes, through the $2^{+}$ of ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$, changes the ratio to 0.24, closer to the theoretical value.

NUCLEAR REACTIONS ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}\mathrm{}(d,t)\mathrm{}$, $E=17\mathrm{}$ MeV; measured $\sigma (E_t;\theta )$. ${}_{}{}^{17}{}_{}{}^{}\mathrm{O}$ levels deduced $S$, ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$(g.s.) deduced wave function; DWBA and CCBA analysis.

The giant electric dipole resonance based on the ground state (${\mathrm{O}}^{+}$) of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ has been studied with the reaction ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}(p,{\gamma }_0){}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ from $E_p=8.6\mathrm{} \mathrm{to} 18.0$ MeV ($E_{\gamma }=20.2\mathrm{} \mathrm{to} 29.0$ MeV). The $E1\mathrm{}$ strength in ($\gamma ,p_0$) is concentrated between $E_{\gamma }=20\mathrm{} \mathrm{and} 29$ MeV where it exhausts about 15% of the $E1\mathrm{}$ sum rule. Major peaks are displayed at 22.2 and 25.0 MeV and secondary structure at 21.0, 22.9, and in the 24 MeV region. The angular distributions indicate predominantly dipole radiation and are fairly constant over the entire range, except in the region of the secondary peaks where the coefficient of $P_2\left(cos\theta \right)$ displays striking interference effects. This behavior supports the suggestion that these structures are due to interference between more complex states and the simple particle-hole configurations of the $E1\mathrm{}$ resonance. The value of the coefficient of $P_2\left(cos\theta \right)$ can be used to restrict greatly the allowed configurations of the $p_0$ channel—the solution is predominantly either $d_{\frac{3}{2}}$ wave or $s_{\frac{1}{2}}$ wave. The presence of terms in $P_1\left(cos\theta \right)$ and $P_3\left(cos\theta \right)$ indicates significant $E2\mathrm{}$ strength which increases above the $E1\mathrm{}$ resonance. Data are also presented on the reactions ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}(p,{\gamma }_1-{\gamma }_4){}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ and ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}(p,\alpha {\gamma }_{15.1}){}_{}{}^{12}{}_{}{}^{}\mathrm{C}$.

NUCLEAR REACTION ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}(p,{\gamma }_0)$, $E=8.6\mathrm{}-18.0$ MeV; measured $\sigma (E;E_{\gamma },\theta )$. Deduced properties ${\gamma }_0$ giant resonance of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$. 99.3% enriched ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$ gas target.

The constraints of unitarity and analyticity on four-body final state amplitudes are studied in the quasi-two-body scheme. The implementation of unitarity with total energy analyticity yields the minimal set of scattering equations for the problem consistent with constraints of quantum mechanics. The minimal set we obtain gives a dynamical scheme which is distinct from the full four-body scattering scheme. Nevertheless, with the assumption of separable approximation for two- and three-body interactions we get simple Lippmann-Schwinger type equations for four identical bosons for the following two-to-two processes: $\mathrm{nt}\to \mathrm{nt}$, $\mathrm{nt}\to \mathrm{dd}$, $\mathrm{dd}\to \mathrm{dd}$, and $\mathrm{dd}\to \mathrm{nd}$. Here $n$, $d$, and $t$ refer to nucleon, deuteron, and triton type states. The amplitudes for the breakup processes can also be related to these amplitudes.

NUCLEAR REACTIONS Four-body final state interaction theory. Useful scattering equations derived from constraints of quantum mechanics.

Angular distributions of the ${}_{}{}^{39}{}_{}{}^{}\mathrm{K}\mathrm{}(p,t)\mathrm{}{}_{}{}^{37}{}_{}{}^{}\mathrm{K}$ and ${}_{}{}^{39}{}_{}{}^{}\mathrm{K}(p,{}_{}{}^3{}_{}{}^{}\mathrm{He}){}_{}{}^{37}{}_{}{}^{}\mathrm{Ar}$ reactions between 3° and 55° have been measured at 40 MeV bombarding energy. The experimental differential cross sections of the transitions to several of the low-lying mirror pairs of even-parity final states in ${}_{}{}^{37}{}_{}{}^{}\mathrm{K}$ and ${}_{}{}^{37}{}_{}{}^{}\mathrm{Ar}$ are compared to results of microscopic distorted-wave Born-approximation calculations based on current shell-model wave functions. The sensitivity of these distorted-wave Born-approximation calculations to optical model parameters is studied.

NUCLEAR REACTIONS ${}_{}{}^{39}{}_{}{}^{}\mathrm{K}\mathrm{}(p,t)\mathrm{}$, ${}_{}{}^{39}{}_{}{}^{}\mathrm{K}(p,{}_{}{}^3{}_{}{}^{}\mathrm{He})$, $E_p=40\mathrm{}$ MeV; measured $\sigma (E_t,E_{3\mathrm{He}},\theta )$; natural target; DWBA analysis.

The low-lying level structure of ${}_{}{}^{233}{}_{}{}^{}\mathrm{U}$ has been studied with the ${}_{}{}^{234}{}_{}{}^{}\mathrm{U}\mathrm{}(d,t)\mathrm{}$ and the ${}_{}{}^{234}{}_{}{}^{}\mathrm{U}({}_{}{}^3{}_{}{}^{}\mathrm{He},\alpha )$ reactions, induced by 14-MeV deuterons and 30-MeV ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ particles, respectively. Levels below 1 MeV of excitation energy are identified and their cross sections are compared with theoretical values, calculated including both Coriolis and $\Delta N=2\mathrm{}$ mixing. Nilsson band assignments are made and discussed.

NUCLEAR REACTIONS ${}_{}{}^{234}{}_{}{}^{}\mathrm{U}\mathrm{}(d,t)\mathrm{}$, $E_{\mathrm{lab}}=14\mathrm{}$ MeV; ${}_{}{}^{234}{}_{}{}^{}\mathrm{U}({}_{}{}^3{}_{}{}^{}\mathrm{He},\alpha )$, $E_{\mathrm{lab}}=30\mathrm{}$ MeV; measured $\sigma \left(\theta \right)$, deduced $l$ values, Nilsson configurations, and level scheme of ${}_{}{}^{233}{}_{}{}^{}\mathrm{U}$.

Energy levels of ${}_{}{}^{239}{}_{}{}^{}\mathrm{U}$ up to an excitation energy of 1.6 MeV have been studied with the ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}\mathrm{}(d,p)\mathrm{}{}_{}{}^{239}{}_{}{}^{}\mathrm{U}$ reaction at a bombarding energy of 12 MeV. Angular distributions $75°\le {\theta }_L<150\mathrm{}°$ provided information on the $l$ values transferred. Level assignments based on the ($d,p$)-data are suggested which partially corroborate recent studies of ${}_{}{}^{239}{}_{}{}^{}\mathrm{U}$ with neutron-capture $\gamma$ rays.

NUCLEAR REACTIONS ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}\mathrm{}(d,p)\mathrm{}$, $E=12\mathrm{}$ MeV; measured $E_x$ and $\sigma \left(\theta \right)$; ${}_{}{}^{239}{}_{}{}^{}\mathrm{U}$ deduced levels, $l$, $J$, $\pi$, Nilsson assignments.

Using electron bremsstrahlung with up to 5.2-MeV end-point energy, the resonant scattering of $\gamma$ rays by an enriched sample of ${}_{}{}^{144}{}_{}{}^{}\mathrm{Sm}$ has been studied. Ground-state transitions were observed from a dozen levels, and the scattering yields, measured at 96° and 126°, were evaluated in terms of radiative widths and level spins. For the strongest excitations, these measurements were supplemented by self-absorption and linear-polarization studies. Some of the observed $E1\mathrm{}$ transitions originate from $1^{-}$ states which, according to isobaric-analog-resonance studies, contain large neutron-particle-hole components. On the other hand, the 3.225- and 3.891-MeV levels, which exhibit the strongest $E1\mathrm{}$ ground-state transitions, occur at energies which suggest that they arise from the coupling of the lowest octupole vibration to the $2_1^{+}$ and $2_2^{+}$ levels.

NUCLEAR REACTIONS ${}_{}{}^{144}{}_{}{}^{}\mathrm{Sm}(\gamma ,\gamma )$, bremsstrahlung $2.0\le E_e\le 5.2$ MeV; measured $\sigma \left(96\mathrm{}°\right)$ and $\sigma \left(126\mathrm{}°\right)$, self-absorption, $\mathrm{LP}$; deduced $\frac{g\Gamma _0^{}{}_{}{}^2}{\Gamma }$, $I$, $\pi$. Enriched target.

In-beam measurements of internal-conversion electrons and $\gamma$ rays from ${}_{}{}^{198}{}_{}{}^{}\mathrm{Hg}(\alpha ,2n){}_{}{}^{200}{}_{}{}^{}\mathrm{Pb}$ are reported. The most recent yrast level scheme, used by several other groups, is found to be in error since the 480-ns state is not primarily deexcited by an 84-keV transition. This transition must instead be ≲ 43 keV. The primary deexcitation of the 158-ns state must be ≲ 50 keV. The 778-keV high-spin transition is measured as $E1\mathrm{}$. The multipole orders of the transitions in the 245→420→462→1026 keV cascade are measured as $E2\mathrm{}$, $E1\mathrm{}$, $E2\mathrm{}$, and $E2\mathrm{}$, respectively.

NUCLEAR REACTIONS ${}_{}{}^{198}{}_{}{}^{}\mathrm{Hg}(\alpha ,2n){}_{}{}^{200}{}_{}{}^{}\mathrm{Pb}$, $E_{\alpha }=30\mathrm{}$ MeV; measured 30-1600-keV internal conversion electron spectra and $\gamma$ spectra in eight time bands in beam. Deduced levels $J$, $\Pi$, ICC. Si(Li) and Ge(Li) detectors.

The differential cross sections for $\alpha$ particles elastically and inelastically scattered from ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ (at 29, 34, 38, and 58 MeV) and elastically scattered from ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}$ (at 29 and 34 MeV), are measured together with excitation functions in the 25-38 MeV region at 178.5° lab. These data together with the data of 26.5, 32.3, 104, and 139 MEV for ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ and 32.3 and 104 MeV for ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}$ from other sources were analyzed using an optical model with volume and surface absorptions and the Saxon-Woods square form factors. The analysis yielded energy dependent depths of both real and imaginary parts of the potential and constant geometric parameters. The analytical expressions for depths of the real and both absorption potentials are obtained. The coupled channel calculations using the above optical potential were performed for the first excited state of ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$. Both elastic scattering data and coupling with the first excited state of ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ are well reproduced using the above potential in the wide scattering energy range.

NUCLEAR REACTIONS ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}\left(\alpha \alpha \right)$, $E=29,34,38,58\mathrm{}$ MeV; ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}\left(\alpha \alpha \right)$, $E=29,34\mathrm{}$ MeV measured $\sigma \left(\theta \right)$, $\sigma \left(178.5\mathrm{}°\right)$ for $E=25\mathrm{}-38$ MeV; deduced optical potential parameters, coupled channel analysis. Enriched targets for ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$, ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}$.

The ($t,{}_{}{}^3{}_{}{}^{}\mathrm{He}$) reactions on ${}_{}{}^{122}{}_{}{}^{}\mathrm{Sn}$ and ${}_{}{}^{124}{}_{}{}^{}\mathrm{Sn}$ have been used to study the masses and the low-lying excited states of ${}_{}{}^{122}{}_{}{}^{}\mathrm{In}$ and ${}_{}{}^{124}{}_{}{}^{}\mathrm{In}$. The ground state $Q$ values as measured here for these two reactions are -6350(50) and -7590(50) keV, respectively, leading to masses of 121.91028(5) and 123.91344(5) u for ${}_{}{}^{122}{}_{}{}^{}\mathrm{In}$ and ${}_{}{}^{124}{}_{}{}^{}\mathrm{In}$. Fourteen excited states of ${}_{}{}^{122}{}_{}{}^{}\mathrm{In}$ with ${\mathrm{E}}_x<1.2\mathrm{}$ MeV and four excited states of ${}_{}{}^{124}{}_{}{}^{}\mathrm{In}$ with ${\mathrm{E}}_{\mathrm{x}}<0.6\mathrm{}$ MeV are also reported. Comparisons are made with $\beta$-decay data.

NUCLEAR REACTIONS ${}_{}{}^{122}{}_{}{}^{}\mathrm{Sn}(t,{}_{}{}^3{}_{}{}^{}\mathrm{He})$, ${}_{}{}^{124}{}_{}{}^{}\mathrm{Sn}(t,{}_{}{}^3{}_{}{}^{}\mathrm{He})$, $E=23.0\mathrm{}$ MeV; measured $\sigma \left(\theta \right)$. ${}_{}{}^{122}{}_{}{}^{}\mathrm{In}$, ${}_{}{}^{124}{}_{}{}^{}\mathrm{In}$ deduced levels. New masses of ${}_{}{}^{122}{}_{}{}^{}\mathrm{In}$, ${}_{}{}^{124}{}_{}{}^{}\mathrm{In}$.

The complex poles and widths of the transition T matrix are determined by the trajectory equations which consist of a set of first order nonlinear differential equations. A heirarchy of approximate solutions to the trajectory equations is developed by iterative methods. The results of this formalism are compared with exact solutions for the case of some strongly interacting pairs of resonances in two iron isotopes. In the presence of intermediate structure the average neutron reaction cross section is interpreted in terms of a resonant strength function which exhibits peaks at neutron energies corresponding to "doorways" levels.

NUCLEAR REACTIONS Complex poles and widths, intermediate structure.

The elastic scattering of $\alpha$ particles near 180° was measured in the vicinity of the Coulomb barrier for ${}_{}{}^{110,112,114,116}{}_{}{}^{}\mathrm{Cd}$, ${}_{}{}^{112,114,116,118,120,122,124}{}_{}{}^{}\mathrm{Sn}$, ${}_{}{}^{122,124,126,128,130}{}_{}{}^{}\mathrm{Te}$, ${}_{}{}^{144,148,150,152}{}_{}{}^{}\mathrm{Sm}$, and ${}_{}{}^{204,206,208}{}_{}{}^{}\mathrm{Pb}$. An optical-model analysis using Woods-Saxon potentials shows that the usual parameters of the real part of the potential $V$, $R_{\mathrm{opt}}$ and $a$ must obey the relationship $V\exp \left[\frac{(R_{\mathrm{opt}}-R_{0.2})}{a}\right]=0.2\mathrm{}$ MeV in order to fit the data. The $\alpha$-nucleus distance $R_{0.2}$ at which the nuclear potential depth is -0.2 MeV can then be determined for each nucleus within ± 0.03 fm. An analysis in terms of a folding model was performed for ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ and ${}_{}{}^{124}{}_{}{}^{}\mathrm{Te}$. For the class of potentials thus obtained, it is the $\alpha$-nucleus distance at 0.5 MeV depth rather than at 0.2 MeV that appears to be best determined. The same analysis determines the radius $R_{\mathrm{FD}}=0.002\mathrm{}$ at which the nucleon density is 2 × ${10}^{-3\mathrm{}}$ nucleon/${\mathrm{fm}}^3$. The value of $R_{\mathrm{FD}}$ is found to depend mostly on the $\alpha$-nucleon effective interaction used, and very little on the functional form of the density distribution. Further evidence is presented in favor of the Gaussian interaction $-U_0\exp (-K^2{r}^2)$ with $U_0=127\mathrm{}$ MeV and $K=0.6\mathrm{}$ ${\mathrm{fm}}^{-1\mathrm{}}$, which has been proposed by Sumner and which leads to the probable value $R_{\mathrm{FD}}=R_{0.2}-(3.06\mathrm{}\pm 0.03)$ fm. Other interactions are not excluded, however, and considering those proposed so far in the literature leads to $R_{\mathrm{FD}}=R_{0.2}-(3.11\mathrm{}\pm 0.14)$ fm. The average variation of $R_{\mathrm{FD}}$ with mass number is found to be $〈R_{\mathrm{FD}}〉=(1.355\mathrm{}{A}^{\frac{1}{3}}+0.87)$ fm for spherical nuclei. The rate of variation of $〈R_{\mathrm{FD}}〉$ with mass number is found to be in good agreement with the droplet model predictions, which is taken as an evidence that the surface thickness of spherical nuclei is practically constant from Sn to Pb.

The magnetic moments of the first $2^{+}$ excited states of even Ni isotopes have been measured using the large dynamic magnetic fields acting on fast ions traversing thin magnetized iron foils. The results obtained are $g({}_{}{}^{58}{}_{}{}^{}\mathrm{Ni},2_1^{+})=-0.06\mathrm{}\pm 0.13$, $g({}_{}{}^{60}{}_{}{}^{}\mathrm{Ni},2_1^{+})=0.09\mathrm{}\pm 0.12$, $g({}_{}{}^{62}{}_{}{}^{}\mathrm{Ni},2_1^{+})=+0.33\mathrm{}\pm 0.12$, and $g({}_{}{}^{64}{}_{}{}^{}\mathrm{Ni},2_1^{+})=+0.45\mathrm{}\pm 0.12$. These results agree with shell-model calculations presented here and contradict previous calculations.

NUCLEAR REACTIONS ${}_{}{}^{58,60,62,64}{}_{}{}^{}\mathrm{Ni}$ (${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$, ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$') ${}_{}{}^{58,60,62,64}{}_{}{}^{}\mathrm{Ni}$ ($2_1^{+}$) $E=72\mathrm{}$ MeV, enriched targets; measured $W(\theta ,H,\infty )$; fast ions in polarized iron. Deduced magnetic moments of $2_1^{+}$ states in ${}_{}{}^{50,60,62,64}{}_{}{}^{}\mathrm{Ni}$.

Several versions of the coupled-equations many-body scattering formalism of Baer, Kouri, Levin, and Tobocman were tested on the generalized Hulbert-Hirschfelder three-body scattering model. In this model two $s$-wave particles interact with an infinite mass scattering center via square well potential forces and with each other via a square well nonlocal force active only in the vicinity of the scattering center. The model exhibits elastic and inelastic scattering, knockout reactions, and knockout with excitation reactions. A convergent level expansion for the collision matrix is provided by wave function matching at the interaction boundaries. This result is compared with $N$-level solutions of the Baer-Kouri and Kouri-Levin versions of the coupled-equations formalism. Kouri-Levin works well for all cases tested while Baer-Kouri works well only for a particular class of cases. When the two particles are treated as indistinguishable fermions, tests may be made of the antisymmetrized forms of the coupled-equations formalism. These proved to be satisfactory. Finally the single cluster approximation to the antisymmetrized Kouri-Levin coupled-equations formalism was tested along with the resonating group method, and both were found to work very poorly for this model.

[NUCLEAR REACTIONS Coupled-equations many-body formalism of Baer, Kouri, Levin, and Tobocman is tested on a soluble three-body model.]

Electrons at five energies between 60 and 120 MeV were used to study the giant electric-dipole and -quadrupole resonances in ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$. Prominent electric-dipole peaks were found at 17.7, 19.1, 20.2, and 23 MeV in good agreement with photoreaction results. In addition our analysis reveals weaker fragmented electric-dipole strength in the region between 12.5 and 15 MeV. Prominent electric-quadrupole peaks were found at 13.0, 13.7, and 16.2 MeV, and a broad peak was found from 14.2 to 15.9 MeV. Two different analyses reveal a broad quadrupole excitation between 16 and 25 MeV. The dipole and quadrupole resonances deplete about 65% and 100% of the energy-weighted sum rule, respectively.

[NUCLEAR REACTIONS ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}(e,e^{\prime })$, $E=59.5, 84,7, 89.8, 109.6, 119.7$ MeV, $q=0.35\mathrm{}$ ∼ 0.9 ${\mathrm{fm}}^{-1\mathrm{}}$, enriched gas target, measured $\sigma \left(E^{\prime }\theta \right)$ up to 25 MeV in excitation energy; deduced dipole and quadrupole strengths in giant resonance region.]

The threshold energy of the ${}_{}{}^{35}{}_{}{}^{}\mathrm{Cl}{\mathrm{}(p,n)\mathrm{}}^{35}$ Ar reaction has been measured to be 6942.2±2.2 keV, clearly resolving the ambiguity arising from two previous conflicting values. The results are discussed in the context of the problems posed by a vanishing Cabibbo angle.

[NUCLEAR REACTIONS ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}\mathrm{}(p,n)\mathrm{}$ $E_p=5770-5840\mathrm{}$ keV, ${}_{}{}^{35}{}_{}{}^{}\mathrm{Cl}\mathrm{}(p,n)\mathrm{}$, $E_p=6910-$ 7000 keV, measured ${\beta }^{+}$ yield; deduced reaction thresholds, Cabibbo angle in ${}_{}{}^{35}{}_{}{}^{}\mathrm{Ar}$.]

The resonating-group method, together with a complex-generator-coordinate technique, is used to investigate the $n$ + ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$ scattering problem. The result shows that, by including a phenomenological imaginary potential in the formulation to take approximate account of reaction effects, a good agreement with experiment can be obtained for both the differential scattering and the total reaction cross sections. The effect of the Pauli principle on the nature of the effective internuclear potential is also examined. Here it is found that the blocking effect, arising from the presence of two nucleons in the nonclosed $1p$ shell of ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$, has a profound influence on the odd-even orbital-angular-momentum dependence of this potential.

[NUCLEAR REACTIONS ${}_{}{}^6{}_{}{}^{}\mathrm{Li}\mathrm{}(n,n)\mathrm{}$; calculated phase shifts and $\sigma \left(\theta \right)$. Resonating-group method with complex-generator-coordinate technique.]