It is shown that the well known phenomenon of the saturation in the B(E2;$0_1^{+}$→$2_1^{+}$), as well as the ${\mathit{E}}_{21}^{+}$ values near midshell in the even rare-earth and actinide nuclei, can be reproduced in the ${\mathit{N}}_{\mathit{p}}$${\mathit{N}}_{\mathit{n}}$ scheme through a very simple parametrization in terms of the maximum number of valence protons and neutrons available in the major shells under consideration. This parametrization leads to a product (${\mathit{N}}_{\mathit{p}}$${\mathit{N}}_{\mathit{n}}$${)}_{\mathit{e}\mathit{f}\mathit{f}}$ which is found to have a more universal character as a structure variable than the usual ${\mathit{N}}_{\mathit{p}}$${\mathit{N}}_{\mathit{n}}$.

We calculate the properties of nuclear matter and neutron matter with charge dependent potentials using the Dirac-Brueckner approach. It turns out that the charge dependence of the NN interaction has no significant influence on the properties of nuclear matter and neutron matter.

The azimuthal distributions of nucleons are studied for central ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$${+}^{51}$V collisions from E/A=35 to 125 MeV based on a Boltzmann equation. We demonstrate that the contribution to azimuthal asymmetry from residue rotation decreases with incident energy and eventually vanishes at energies E/A≥75 MeV. In contrast, the contribution from the directed transverse motion remains important throughout the energy range investigated. We show that the disappearance of rotation is mainly caused by the onset of multifragmentation for which the thermal instabilities appear to play a minor role.

Different normalization conditions for random phase approximation amplitudes have been obtained recently for use with energy-dependent interactions. These conditions are shown to be equivalent. A third method, which has a wider applicability, is also discussed.

The ${}_{}{}^{16}{}_{}{}^{}\mathrm{-}_{}^{40}{}_{}{}^{}$Ca imaginary potential of Andres, Catara, and Lanza presents a surprising behavior in terms of the incident energy and is abnormally weak. We show that this is due to, first, the neglect of important inelastic channels corresponding to the excitation of low-lying $2^{+}$, $4^{+}$, and $5^{\mathrm{-}}$ collective states, and, second, a possible underestimation of the contribution due to the excitation of the low-lying $3^{\mathrm{-}}$ states.

This is a reply to the preceding Comment. We confirm the results of our paper. The differences between our calculations and those of the preceding Comment come mainly from the form factors. Our random-phase-approximation–based form factors are in good agreement with those obtained by using experimental transition densities.

We reply to the Comment of von Neumann-Cosel et al. [Phys. Rev. C 44, 554 (1991)]. Some of our results were quoted incorrectly in the Comment; the correct values are listed in Table I. We extend the analysis of the Comment by also discussing our most recent result for ${}_{}{}^{115}{}_{}{}^{}\mathrm{In}$. An experimental investigation of Monte Carlo predictions made in the Comment shows that the intensity of additional environmental Compton scattering is seriously overestimated.

The spatial and temporal extent of a system decaying by multifragment emission is deduced. Two-particle intermediate mass fragment correlation functions measured for central ${}_{}{}^{36}{}_{}{}^{}\mathrm{Ar}$${+}^{197}$Au collisions at E/A=50–110 MeV indicate a rapid decay, <75 fm/c, of the highly excited system. Furthermore, the behavior of the correlation function at large relative velocities suggests that considerable charge loss occurs prior to fragment emission.

Application of a large-volume NaI scintillator to search for the cold dark matter (DM) in the Universe is discussed. A low-noise (∼5 keV) and low-background (∼5/keV kg day) were achieved even with a large (36.5 kg) NaI scintillator. Light output efficiencies for ${}_{}{}^{23}{}_{}{}^{}\mathrm{Na}$ and ${}_{}{}^{127}{}_{}{}^{}\mathrm{I}$ were measured as 0.4±0.2 and 0.05±0.02, in the recoil energy range of 5–100 keV and 40–300 keV, respectively. NaI is shown to have merits of a large volume, large scattering cross sections for dark matter, and of 100% abundance of finite-spin nucleus, but to have the demerits of a small form factor due to the finite-size effect of ${}_{}{}^{127}{}_{}{}^{}\mathrm{I}$ at the presently measured energy region.

Both two-deuteron and two-proton correlation functions, at small relative momenta, have been measured for ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$${+}^{27}$Al collisions at E/A=75 MeV. Data are compared to the predictions of a microscopic transport model which incorporates deuteron production and Coulomb interactions. The results indicate that deuterons are emitted over a shorter time span than protons.

Observation of γ-γ coincidences from the reaction ${}_{}{}^{124}{}_{}{}^{}\mathrm{Sn}$${(}^{24}$Mg,xn) at 145 MeV has revealed a discrete superdeformed rotational band and evidence of a superdeformed continuum in ${}_{}{}^{142}{}_{}{}^{}\mathrm{Sm}$. This result is consistent with cranked shell model calculations indicating shell gaps favorable to superdeformed structures in N=80, Z∼64 nuclei. It is proposed that the ${}_{}{}^{142}{}_{}{}^{}\mathrm{Sm}$ band may be described by a proton hole in an ${}_{}{}^{143}{}_{}{}^{}\mathrm{Eu}$ core. The dynamic moment of inertia of the superdeformed band is more constant than predicted by the model. This may be due to a strong residual interaction between a $6_1$ proton intruder and aligning N=6 valence neutrons.

The effects of deformation on sub-barrier fusion were first demonsrated almost fifteen years ago. Since that first analysis, it has become generally accepted that quadrupole deformation parameters deduced from fusion are significantly lower than those deduced from Coulomb excitation. Following a detailed analysis of the excitation function for ${}_{}{}^{154}{}_{}{}^{}\mathrm{Sm}$${+}^{16}$O we find the excitation function is best fitted with deformation parameters which are consistent with Coulomb excitation data when a sufficiently complete model is used. The shape of the deduced barrier distribution strongly favors the inclusion of a positive hexadecapole moment.

A highly deformed rotational band has been observed in the odd-odd nucleus ${}_{}{}^{136}{}_{}{}^{}\mathrm{Pm}$. This band sheds important new light on the anomalous behavior of the dynamical moments of inertia of rotational bands previously observed in the Ce-Nd-Sm A∼135 superdeformed region which has been a theoretical puzzle for several years.

We argue in this work that significant ambiguities exist with respect to the (e,e’p) reaction mechanism. This is based on an analysis of the systematic behavior with ${\mathit{Q}}^2$ and opening angle of new and existing (e,e’p) data. The analysis implies a consequent uncertainty in the interpretation of color transparency experiments that integrate over a large (≳50 MeV) missing energy range.

Total cross section extractions are sometimes based on extrapolations of in-plane data to unobserved regions of phase space. The total cross section can then only be derived if assumptions are made about the distributions of the independent phase space variables. In the case of the reaction ${\mathrm{\pi }}^{\mathrm{-}}$p→${\mathrm{\pi }}^{+}$${\mathrm{\pi }}^{\mathrm{-}}$n an out-of-plane measurement, performed by our group, indicates that these assumptions made by some experimenters are partially not supported by the data.

The scattering of ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ on ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ and on its mirror nucleus ${}_{}{}^{13}{}_{}{}^{}\mathrm{N}$ is considered in the framework of a four-body model with two (inert) ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ cores and a pair of weakly bound nucleons. Numerical calculations of the elastic angular distributions for the two systems show that the surface transparency of the core-core interaction and the weak binding of the proton in ${}_{}{}^{13}{}_{}{}^{}\mathrm{N}$ will enable one to extract the effective neutron-proton interaction from analyses of the ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$${+}^{13}$N elastic scattering.

Mean-field approximation results emerging from Hartree-Fock calculations with Skyrme-type forces are compared with those obtained within the natural orbital representation of the Jastrow correlation method in its lowest order approximation for ${}_{}{}^4{}_{}{}^{}\mathrm{He}$, ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ and ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$. The influence of short-range correlations on the single-particle wave functions and occupation probabilities is analyzed. A two part decomposition of the one-body density matrix is achieved which reflects both the low- and high-momentum components of the correlated ground state.

Measurements of the spin-dependent asymmetry in scattering longitudinally polarized electrons from polarized ${\mathrm{He}}^3$ at quasielastic kinematics are reported. The measurements were made at two kinematics and spin angles, one sensitive to the helicity-dependent transverse-longitudinal interference response function, ${\mathrm{R}}_{\mathrm{TL}\prime }$, and the other to the helicity-dependent transverse response function, ${\mathrm{R}}_{\mathrm{T}\prime }$. For the experiment a metastability exchange optically pumped polarized ${\mathrm{He}}^3$ target was used; a general discussion of the technique used to polarized the ${\mathrm{He}}^3$, along with the details of the design and operation of the target system, are presented here. A comparison is made of the world’s data on the He${\to }^3$(e→,e′) quasielastic asymmetry with several theoretical predictions, including calculations that use the plane wave impulse approximation and a fully spin-dependent spectral function. There is good agreement between data and theory at the current level of experimental precision.