The two-body spin-orbit term in the nucleon-nucleon transition operator responsible for intermediate-energy nucleon-nucleus inelastic scattering is studied. It is shown that the simple characteristic energy dependence of the spin-orbit contribution at fixed momentum transfer $q$ is largely maintained in the presence of antisymmetrization, distortion, and other energy-dependent effects. Fixed-$q$ variable-energy plots of cross sections may therefore be useful as a diagnostic tool for important spin-orbit contributions for isoscalar transitions in the range $100\le E_p\le 400$ MeV.

NUCLEAR REACTIONS Effective spin-orbit interaction in inelastic nucleon-nucleus scattering. Energy-dependent signature at fixed momentum transfer.

This work draws an analogy between a heated nucleus breaking up into clusters and a liquid undergoing a phase transition to a gas in which droplets appear. The critical temperature and density in the nucleus are investigated using a Skyrme effective interaction and finite temperature Hartree-Fock theory. The energy and pressure as a function of density are calculated. The effects of compressibility, effective mass, and binding energy per particle on the critical temperature and critical density of nuclear systems is developed. In some cases, analytic expressions for these quantities can be obtained.

NUCLEAR REACTIONS Phase transitions in hot nuclear matter.

We consider the longitudinal and transverse response functions for quasielastic electron scattering from ${}_{}{}^{56}{}_{}{}^{}\mathrm{Fe}$. In a previous work we showed that the longitudinal response is overestimated by about forty percent in the impulse approximation. We argued that shortrange correlations, among other effects, could shift transition strength to higher energies. To account for these features we multiplied the cross sections by a factor $Z^2$, where $Z$ is a measure of the strength of the quasiparticle pole. The model we proposed then led to a significant underestimate of the transverse response. In this work we concentrate on the analysis of the transverse response and consider the electromagnetic properties of an interacting system of nucleons and deltas. Specific assumptions concerning the transition amplitudes $N{N}^{-1\mathrm{}}\to N{N}^{-1\mathrm{}}$ and $N{N}^{-1\mathrm{}}\to \Delta N^{-1\mathrm{}}$ allow for a simultaneous fit to both the longitudinal and transverse response functions. In our model the amplitude $N{N}^{-1\mathrm{}}\to \Delta N^{-1\mathrm{}}$ is governed by rho exchange with no additional correlation corrections. The model further requires that the $N{N}^{-1\mathrm{}}\to N{N}^{-1\mathrm{}}$ amplitude be small for the momentum transfers considered here: $210 \mathrm{MeV}/c\le \left|\overrightarrow{\mathrm{q}}\right|\le 410 \mathrm{MeV}/c$. Some theoretical support is offered for these small values of the latter amplitude.

NUCLEAR REACTIONS Quasielastic electron scattering; transverse and longitudinal response functions; effective forces in nuclei at intermediate momentum transfer.

The ${\pi }^{-}$-atom and low-energy $\pi$-nucleus elastic scattering data have been analyzed systematically in order to examine their information content with respect to the structure of the $\pi$-nucleus optical potential. We have firmly established the existence of the data's insensitivity to the potential structure and have examined its consequences in detail. The insensitivity is manifested in the form of correlations between the coefficients of $\rho$ and ${\rho }^2$ in the potential. We have found that such correlations vary slowly as a function of the pion energy ($T_{\pi }$) from the threshold (the ${\pi }^{-}$ atoms) through 50 MeV and that, exploiting the correlations, one can define an effective nuclear density, ${\rho }_e$, at which the pion effectively interacts with nuclei. ${\rho }_e$ was also found to increase slowly as $T_{\pi }$ increases. In contrast, no correlation was observed between the coefficient of the local term and that of the nonlocal (momentum dependent) term. As a consequence of the above nature of the correlations, we have established a form of the optical potential which contains the minimum number of parameters in order to describe the information content of the data.

NUCLEAR REACTIONS Unified analysis; strong-interaction shifts and widths in ${\pi }^{-}$ atoms and differential cross sections of elastic $\pi$-nucleus scatterings up to 50 MeV; effective nuclear density; $\pi$-nucleus optical potentials.

Using the method of effective nuclear density, we apply a simple, $\pi$-nucleus optical potential (without ${\rho }^2$ terms and the Lorentz-Lorenz effect) to ${\pi }^{-}$ atoms and low-energy $\pi$-nucleus elastic scatterings. Data of both phenomena are analyzed in a unified, hybrid (phenomeno-logical and theoretical) manner: The ${\pi }^{-}$-atom data are analyzed first to determine phenomenologically the potential parameters at threshold. The parameters are then extrapolated successfully up to 50 MeV incident pion laboratory energy by a microscopic calculation in which the energy-dependence correction is made after including the Fermi-averaging and Pauli-blocking effects. In contrast to other work, our potential includes the minimum number of the parameters that describe the full information content of the data. We can thus conclude that these effects are the important microscopic corrections for the extrapolation, but neither the Lorentz-Lorenz effect nor some highly nonlocal effects are crucial ones. The potential we have used has angular transformation terms which are also found to be crucial in the unified treatment. During the course of this work we have found an interesting behavior of the terms. A short account of its discussion is also presented.

NUCLEAR REACTIONS Unified analysis and calculation; strong-interaction shifts and widths in ${\pi }^{-}$ atoms and differential cross sections of elastic $\pi$-nucleus scattering up to 50 MeV; $\pi$-nucleus optical potential.

We have studied transitions weakly fed in the ${\beta }^{+}$ decays of ${}_{}{}^{18}{}_{}{}^{}\mathrm{Ne}$ and ${}_{}{}^{19}{}_{}{}^{}\mathrm{Ne}$. The ${}_{}{}^{18}{}_{}{}^{}\mathrm{Ne}$ activity was produced by bombarding natural ${\mathrm{O}}_2$ gas with 12.0 MeV ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ ions. $\gamma$-ray groups with energies of 659, 1042, 1081, and 1700 keV were observed with relative intensities of 1.72±0.05, 100.0, (2.89±0.26)×${10}^{-2\mathrm{}}$, and 0.687±0.013, respectively. These intensities correspond to relative branching ratios of 100.0, (2.70±0.36)×${10}^{-2\mathrm{}}$, and 2.45±0.05 for ${\beta }^{+}$ transitions to the 1042, 1081, and 1700 keV levels, respectively. Normalizing to previous data we obtain $\mathrm{ft}$ values of 1247±11, 2971±87, (1.03±0.14)×${10}^7$, and (3.00±0.10)×${10}^4$ see for the transitions to the ground state, 1042, 1081, and 1700 keV levels, respectively. The difference in excitation energies of the $0^{-}$ and $0^{+}$ states is found to be 39.20±0.11 keV. The ${}_{}{}^{19}{}_{}{}^{}\mathrm{Ne}$ activity was produced by bombarding S${\mathrm{F}}_6$ gas by 6.4 MeV protons. A branching ratio of (1.20±0.20)×${10}^{-4\mathrm{}}$ was obtained for the transition to the 110 keV level which corresponds to an $\mathrm{ft}$ value of (1.15±0.19)×${10}^7$ sec. Transitions to the 1554 keV level were observed in a 9.2% Ge(Li) detector operated in the singles mode. A branching ratio of (2.34±0.30)×${10}^{-5\mathrm{}}$ was obtained which corresponds to an $\mathrm{ft}$ value of (5.01±0.47)×${10}^5$ sec. The ${}_{}{}^{18}{}_{}{}^{}\mathrm{Ne}$($0^{+}$; 1)→${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$(1081 keV $0^{-}$; 0) and ${}_{}{}^{19}{}_{}{}^{}\mathrm{Ne}$(${\mathrm{½}}^{+}$; ½)→${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$ (110 keV ${\mathrm{½}}^{-}$; ½) first-forbidden ${\beta }^{+}$ branches are analogs of the previously measured parity mixing of the 1042 keV ($0^{+}$; 1) and 1081 ($0^{-}$; 1) keV levels of ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ and of the ground (${\mathrm{½}}^{+}$; ½) and 110 keV (${\mathrm{½}}^{-}$; ½) levels of ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$, respectively. We show that the strong exchange-current corrections to the axial charge operator dominating these $\beta$ transitions involve an operator identical, apart from an isospin rotation, to that mediating the pion-exchange contribution to the parity nonconserving $\mathrm{NN}$ force. These exchange current contributions can be extracted from the $\beta$-decay rates in a manner nearly independent of nuclear structure assumptions. Thus, in these cases, the usual structure uncertainties that obscure the connection between the $\Delta S=0\mathrm{}$ weak hadronic interaction and nuclear observables can largely be circumvented. The $\mathrm{ft}$ values we obtain for the transitions to the 1081 keV and 110 keV levels of ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ and ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$ suggest that the strengths of the $I=1\mathrm{}$ and $I=0\mathrm{}$ components of the parity nonconserving $\mathrm{NN}$ force are close to the "best values" of Desplanques, Donoghue, and Holstein. Except for a recent structure calculation employing complete $2h\omega$ and $1h\omega$ bases for the positive and negative parity states in ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$, the $\beta$ decay and parity nonconserving matrix elements predicted in typical shell model studies are approximately three times larger than experiment. This and other evidence suggests that the softening of the nuclear Fermi surface by $2h\omega$ configurations is an essential, but missing, feature of most nuclear structure calculations of parity nonconserving matrix elements. We conclude by presenting shell model studies of the electromagnetic properties of low-lying states in ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$, ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$/${}_{}{}^{19}{}_{}{}^{}\mathrm{Ne}$, and ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$/${}_{}{}^{21}{}_{}{}^{}\mathrm{Na}$ as well as the matrix elements for the operators that arise in a general meson-exchange parity nonconserving potential.

RADIOACTIVITY ${}_{}{}^{18}{}_{}{}^{}\mathrm{Ne}$, ${}_{}{}^{19}{}_{}{}^{}\mathrm{Ne}$; measured $I\gamma$; deduced $\mathrm{ft}$. Compared to shell model calculations. Discussed connection of forbidden decays to parity mixing in ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ and ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$.

The previously unreported decay of ${}_{}{}^{152}{}_{}{}^{}\mathrm{Pr}$ to levels in ${}_{}{}^{152}{}_{}{}^{}\mathrm{Nd}$ has been studied from mass-separated activity produced in the thermal neutron fission of ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}$. The ${}_{}{}^{152}{}_{}{}^{}\mathrm{Pr}$ half-life was measured to be 3.24±0.19 s, and its decay scheme was constructed based on $\gamma$ singles and coincidence measurements. Excited states in ${}_{}{}^{152}{}_{}{}^{}\mathrm{Nd}$ at 72.6 ($2^{+}$) and 236.6 ($4^{+}$) were established and the $\frac{E\left(4^{+}\right)}{E\left(2^{+}\right)}$ ratio of 3.26 is close to the rigid rotor value of 3.33. The implications of the above ratio for the systematics of deformation in this region are discussed. A $\gamma$ transition observed at 285.0 keV probably results from the ${\beta }^{-}$ decay of ${}_{}{}^{152}{}_{}{}^{}\mathrm{Ce}$ with a half-life of 3.1±0.3 s, but that conclusion is tentative. The most likely $J$ for the ${}_{}{}^{152}{}_{}{}^{}\mathrm{Pr}$ ground state is 3.

RADIOACTIVITY ${}_{}{}^{152}{}_{}{}^{}\mathrm{Pr}$ and ${}_{}{}^{152}{}_{}{}^{}\mathrm{Ce}$ [from ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}(n, f)$]; measured $T_{\frac{1}{2}}$, $E_{\gamma }$, $I_{\gamma }$, $\gamma \gamma$, and $\gamma X$ coin, Ge(Li) detectors; ${}_{}{}^{152}{}_{}{}^{}\mathrm{Nd}$ and ${}_{}{}^{152}{}_{}{}^{}\mathrm{Pr}$ deduced levels, $J$, $\pi$, $log\mathrm{ft}$. Mass separated ${}_{}{}^{152}{}_{}{}^{}\mathrm{Pr}$ and ${}_{}{}^{152}{}_{}{}^{}\mathrm{Ce}$ activity.

Gamma-ray angular correlation measurements have led to a definite identification of the 2084.5-keV level as the first-excited $0^{+}$ state in ${}_{}{}^{144}{}_{}{}^{}\mathrm{Nd}$. This level is in good accord with the predictions of both the unified model and the interacting boson approximation model.

RADIOACTIVITY ${}_{}{}^{144}{}_{}{}^{}\mathrm{Pr}$ (${\beta }^{-}$); measured $\gamma \gamma \left(\theta \right)$. ${}_{}{}^{144}{}_{}{}^{}\mathrm{Nd}$ deduced levels, $J$. NaI(Tl)-Ge(Li) combination.

NUCLEAR REACTIONS ${}_{}{}^{144}{}_{}{}^{}\mathrm{Nd}$; calculated levels, $J$, $\pi$, electromagnetic properties. Interacting boson approximation model.

The ${\beta }^{-}$ decay of ${}_{}{}^{102}{}_{}{}^{}\mathrm{Y}$ to levels in ${}_{}{}^{102}{}_{}{}^{}\mathrm{Zr}$ was investigated from sources produced in the thermal neutron induced fission of ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}$ and separated using a gas-filled recoil separator. Singles and coincidence $\gamma$ and x ray measurements were carried out. Only one $\beta$ decaying level of ${}_{}{}^{102}{}_{}{}^{}\mathrm{Y}$ was observed with a half-life of 0.36±0.04 s. A total of seven $\gamma$ transitions was placed in a level scheme consisting of excited states in ${}_{}{}^{102}{}_{}{}^{}\mathrm{Zr}$ at 152 ($2^{+}$), 478 ($4^{+}$), 731, 891, 965 ($6^{+}$), 1538, and 1823 keV. The results are compared with those from fission fragment studies and a calculation based on a deformed quasiparticle basis. Implications for the systematics of even-even Zr nuclides with mass numbers around 100 are discussed.

RADIOACTIVITY ${}_{}{}^{102}{}_{}{}^{}\mathrm{Y}$ [from ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}(n, f)$]; measured $T_{\frac{1}{2}}$, $E_{\gamma }$, $I_{\gamma }$, $\gamma \gamma$, and $x\gamma \mathrm{coin}$, Ge(Li) detectors; ${}_{}{}^{102}{}_{}{}^{}\mathrm{Zr}$ deduced levels, $J$, $\pi$. Mass and charge separated ${}_{}{}^{102}{}_{}{}^{}\mathrm{Y}$ activity.

The probability for $K$-shell ionization in the positron decay of ${}_{}{}^{65}{}_{}{}^{}\mathrm{Zn}$, $P_K\left({\beta }^{+}\right)$ has been studied by recording coincidences between the annihilation radiation produced subsequent to the positron decay and the Cu $K$ x rays produced when the $K$-shell vacancy is filled. This probability was found to be (16.1±3.0)×${10}^{-4\mathrm{}}$, which is approximately three times larger than recent theoretical predictions of Law and Suzuki.

RADIOACTIVITY Measured Cu $K$ x rays in coincidence with annihilation photons in the ${\beta }^{+}$ decay of ${}_{}{}^{65}{}_{}{}^{}\mathrm{Zn}$; deduced $K$-shell ionization probability.

The probability per $K$ capture for double $K$-shell ionization in the electron capture decay branches of ${}_{}{}^{65}{}_{}{}^{}\mathrm{Zn}$ has been studied by recording coincidences between Cu $K$ x rays and Cu $K\alpha$ x rays produced when the two $K$ shell vacancies are filled. A combined probability for the two decay branches was found to be (2.2±0.2)×${10}^{-4\mathrm{}}$, a value which is approximately a factor of 1.5 greater than recent theoretical predictions by Suzuki and Law. The energy shift of the hypersatellite Cu $K{\alpha }^H$ x ray was found to be (321±17) eV.

RADIOACTIVITY Measured Cu $K$ x-ray—$K\alpha$ x-ray coincidences in electron capture decays of ${}_{}{}^{65}{}_{}{}^{}\mathrm{Zn}$; deduced combined double $K$-shell ionization probability and hypersatellite $K{\alpha }^H$ x-ray shift.

Spectral distribution calculations of the separate positive and negative parity level densities and spin cutoff parameters for ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ have been made in an $\mathrm{sdf}$ basis. A configuration expansion utilizing higher moments of the Hamiltonian is found to be important in improving agreement between calculation and experiment at low excitation energies. The Hamiltonian moments were corrected for the effects of spurious c.m. motion. The present results suggest that spectral distribution calculations can yield level densities which agree with experimental information on the number of levels, spin cutoff factors, and parity ratios over an energy range of over 20 MeV.

NUCLEAR STRUCTURE ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$; calculated level density and spin cutoff parameter 0-25 MeV.

The structure of high-lying states in ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ has been studied using the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{12}{}_{}{}^{}\mathrm{C}, \alpha ){}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ reaction at $E\left({}_{}{}^{12}{}_{}{}^{}\mathrm{C}\right)=64\mathrm{} \mathrm{and} 80$ MeV. The spins and branching ratios to the $\alpha$ +${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ channel were determined by measuring double ($\alpha -\alpha$) and triple ($\alpha -\alpha -\gamma$) angular correlations. The branching ratios for decay to the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ + ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$ channel were obtained from an $\alpha$-${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ coincidence experiment. In addition to confirming the spins of several lower-lying states, we have made a spin assignment of $8^{+}$ for the state at 18.538 MeV and also suggest assignments to states at 17.259 MeV ($7^{-}$), 20.478 MeV ($8^{+}$), and 24.378 MeV ($7^{-}$). The 13.927-MeV ($6^{+}$) state is assigned to the $K^{\pi }=0_2^{+}$ band, and it is suggested that this band also includes the $8^{+}$ state at 20.478 MeV. The 18.538-MeV ($8^{+}$) state was found to have a large reduced width for decay into ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ + ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$ which, together with its small reduced width for decay to $\alpha$ +${}_{}{}^{16}{}_{}{}^{}\mathrm{O}_{\mathrm{g}.\mathrm{s}.\mathrm{}}^{}{}_{}{}^{}$,suggests that it has a large ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ + ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$ cluster parentage. This state appears to be the $8^{+}$ member of a new 8p-4h band which has the 12.436-MeV ($0_6^{+}$) state as its band head and the state at 15.159 MeV as its $6^{+}$ member. The discovery of such a rotational band in ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ with a large ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ + ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$ cluster parentage and a large moment of inertia provides the first direct indication of correlations between the α clusters in 8p-4h states.

NUCLEAR STRUCTURE ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$; measured spins, parities, branches to $\alpha$ +${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ and ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ + ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$; deduced reduced widths, cluster structure.

We propose a three-body potential among alpha particles based on a single ${\alpha }^{*}$ excitation and adjust its parameters so that the experimental binding energy and charge radius of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ in the $3-\alpha$ model is obtained. With this potential we calculate the elastic and the $0_1^{+}$→$0_2^{+}$ inelastic form factor and reduced transition probabilities. The three-body potential in conjunction with an Ali-Bodmer two-body potential yields a satisfactory fit to the $0_1^{+}$→$0_2^{+}$ inelastic form factor and a very good agreement with the measured reduced transition probability.

NUCLEAR STRUCTURE $3-\alpha$ model of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, three-body potential among alpha particles, elastic and inelastic form factors of electron scattering, reduced transition probabilities.

The alpha amplitudes are calculated for various low-lying positive parity states of ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$. It is shown that the results obtained from the oscillator with equal size parameter ($\omega ={\omega }^{\prime }$) are singular ones. They are, in general, not reproduced in the limit $\omega \to {\omega }^{\prime }$. The proper consideration of this point leads to new results. In particular, the SU(3) states $\left|\right(\lambda , \mu )〉$ with $\mu \ne 0$ may have nonvanishing alpha amplitudes.

NUCLEAR STRUCTURE $\alpha$-spectroscopic factor for ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ states.

Low order calculations for the energy and density of model nuclear matter are carried out which make use of correlation functions $f\left(r\right)\mathrm{}$ obtained by means of a differential equation. This is derived by variation of the two-body energy functional subject to the well known healing condition ($\rho \int {\mathrm{}[1-f(r\left)\right]}^{2}D\left(r\right)d\overrightarrow{\mathrm{r}}=c, c$ a small constant). The problem of the determination of the corresponding Lagrangian multiplier has been investigated and we have concluded to determine it from the less deep minimum of the ratio $\left|\frac{E^{\mathrm{}\left(3\right)\mathrm{}}}{E^{\mathrm{}\left(2\right)\mathrm{}}}\right|$ of the third to the second term of the factorized Iwamoto-Yamada expansion of the energy. In addition, the corresponding condition for the minimum has been studied. Results for the values of the energy (which has been approximated by the first three terms of the factorized Iwamoto-Yamada expansion), the density, and several convergence quantities have been obtained with the test potentials of Iwamoto and Yamada and Ohmura, Morita, and Yamada. Compared to other results from low and high order calculations, it is seen that those of the density are similar, but those for the energy are smaller in our case, suggesting that correlation functions quite constrained have been obtained. The possibility of improvements is finally considered.

NUCLEAR STRUCTURE Correlation function, binding energy, and Fermi momentum of nuclear matter. Low order calculation, healing condition.

The principal series approximation is extended to the description of two correlated quasiparticles states, enabling a treatment of these states that takes into account the coupling among the two particle Green's function and the particle-hole one. This description is related to a random phase approximation treatment of collective states in open shell nuclei that includes simultaneously the particle-particle and particle-hole versions of the nuclear residual Hamiltonian. Using separable interactions it is found that the inclusion of the particle-particle part of the Hamiltonians greatly changes the properties of the$2^{+}$ states in the Sn isotopes.

NUCLEAR STRUCTURE Collective excitations in superconductive nuclei. Multipole separable forces. The $0^{+}$ spurious state. The $2^{+}$ state in tin isotopes.

The multiphonon method is applied to heavy nuclei using the collective $K=0^{-}$ octupole state as the building phonon. A good description of the $K=0^{-}$ band is possible even at low energy $E$ where the random-phase approximation fails. It also becomes clear why one has not observed $K=0^{+}$ states with an energy of the order of $2E$.

NUCLEAR STRUCTURE Multiphonon states of octupole nature in even-even deformed nuclei with mass number $222\le A\le 228$.

We present the results of a decomposition of the angular distribution of the continuum observed in the ${}_{}{}^{90}{}_{}{}^{}\mathrm{Zr}(p, n)$ reaction at 200 MeV into different angular momentum transfers. We found significant amounts of $L=0\mathrm{}$ strength over a wide range of excitation energies in the continuum, which sums up to more than half of the missing Gamow-Teller strength.

NUCLEAR REACTIONS Continuum Gamow-Teller strength in ($p, n$) reaction.

Strong mirror channel correlations have been observed in the reactions ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, p){}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, p){}_{}{}^{21}{}_{}{}^{}\mathrm{Na}$. The linear cross correlation coefficient $r$ is found to be of the order of 0.6, indicating a high degree of isospin conservation. For the compound nucleus ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ the isospin mixing matrix element $〈V_c〉$ is estimated to be about 1 keV at $E_x\cong 19$ MeV.

NUCLEAR REACTIONS ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, p){}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$, ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, n\gamma ){}_{}{}^{21}{}_{}{}^{}\mathrm{Na}$; $E=4.0-8.0\mathrm{}$ MeV; measured $\sigma (E, \theta )$. ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ deduced isospin mixing. Hauser-Feshbach calculations.