Theoretical predictions for the deuteron and the isoscalar trinucleon charge form factors are compared. Correlations between them are found. Linear relations hold for the position of the diffraction minimum and for the position and height of the secondary maximum. The linear relation for the diffraction minimum does not pass through the experimental data.

Dilepton production from pion-pion annihilation in a hot hadronic matter is studied using an effective chiral Lagrangian that includes explicitly vector mesons. We find that the production rate for dileptons with invariant masses around the ρ-meson resonance is suppressed as a result of the modification of the pion electromagnetic form factor at finite temperature. The relevance of this phenomenon to the partial restoration of chiral symmetry in hot hadronic matter is discussed.

Within the framework of random walk model, a method of simulation is proposed for introducing fluctuations in BUU dynamics. To overcome the difficulties that arise due to the fermionic nature of the colliding particles, the underlying stochastic process is considered to be dichotomic in nature so that the phase cell occupancy is taken as either 0 or 1. As a result, the associated variance always satisfies the expected quantum mechanical results. The method is illustrated and tested for a well-studied two-dimensional scenario.

Pion-nucleus total cross sections are examined for pion laboratory kinetic energies between 400 MeV and 1 GeV. Modifications by the nuclear medium of the dominant ${\mathrm{D}}_{13}$(1520) and ${\mathrm{F}}_{15}$(1680) excited hadrons are investigated. Fermi motion and multiple scattering are found to broaden significantly the peaks in the cross section. Additional broadening as determined from a model of photon-nucleus total cross sections is found to further reduce the cross sections and increase the discrepancy between theory and data. The discrepancy, nearly energy-independent and of the order of 15–20 %, can be accounted for if one assumes the nuclear medium causes a 31–42 % increase in the strength of the pion-nucleon interaction in all channels.

We estimate the numbers and mass spectra of observed lepton and kaon pairs produced from φ meson decays in the central rapidity region of an Au+Au collision at lab energy 11.6 GeV/nucleon. The following effects are considered: possible mass shifts, thermal broadening due to collisions with hadronic resonances, and superheating of the resonance gas. Changes in the dilepton mass spectrum may be seen, but changes in the dikaon spectrum are too small to be detectable.

The ${}_{}{}^{108}{}_{}{}^{}\mathrm{Ag}$ nucleus has been studied by in-beam γ spectroscopy with the heavy-ion fusion-evaporation reaction ${}_{}{}^{100}{}_{}{}^{}\mathrm{Mo}$${(}^{11}$B,3nγ) at 39 MeV. Excitation functions, γ-γ-t coincidences, angular distributions, and DCOQ ratios were measured. A level scheme has been constructed and various bands have been identified with characteristics similar to those in other A≊100 nuclei. Total Routhian surface calculations predict prolate axially symmetric shapes with collective and noncolllective character and satisfactorily account for most of the experimental results.

The new neutron-deficient isotopes ${}_{}{}^{210}{}_{}{}^{}\mathrm{Th}$ and ${}_{}{}^{211}{}_{}{}^{}\mathrm{Th}$ have been produced in fusion reactions with 5.2–5.7 MeV/nucleon ${}_{}{}^{35}{}_{}{}^{}\mathrm{Cl}$ ions on ${}_{}{}^{181}{}_{}{}^{}\mathrm{Ta}$. The activities were identified on the basis of correlated α decay chains. Fusion evaporation products were separated in-flight using a gas-filled magnetic recoil separator. The measured α energies of ${}_{}{}^{211}{}_{}{}^{}\mathrm{Th}$ and ${}_{}{}^{210}{}_{}{}^{}\mathrm{Th}$ are (7792±14) and (7899±17) keV, respectively. The half-lives were found to be (${37}_{\mathrm{-}11}^{+28\mathrm{}}$) ms ${(}^{211}$Th) and ($9_{\mathrm{-}4}^{+17\mathrm{}}$) ms ${(}^{210}$Th).

Recent experimental data on positive-parity yrast states, based on the π${\mathit{h}}_{11/2}$⊗ν${\mathit{h}}_{11/2}$ configuration, of odd-odd ${}_{}{}^{128,130,132,134}{}_{}{}^{}\mathrm{La}$ are compared in a systematic way with the energies and transition probabilities calculated within the framework of the two quasiparticle, axially symmetric core model. It is found that very good agreement is obtained in ${}_{}{}^{128,130}{}_{}{}^{}\mathrm{La}$ assuming prolate deformation. Influence of the neutron Fermi level on the level properties in these two nuclei has also been studied. In the case of ${}_{}{}^{132,134}{}_{}{}^{}\mathrm{La}$, this model seems to indicate that this positive parity yrast band may have an oblate deformation.

The ${}_{}{}^{122}{}_{}{}^{}\mathrm{Xe}$ nucleus is investigated using statistical theory for studying intrinsic properties as a function of temperature and spin assuming the nucleus to move in a triaxially deformed Nilsson potential. The single particle level density parameter is extracted as a function of temperature for various spins and is found to reach a constant value at higher temperature. The excitation energy is calculated as a function of angular momentum for different entropies and temperatures. The spin cutoff parameter as a function of angular momentum is determined for various temperatures from the rotational energy. The shell correction as a function of angular momentum is determined. The variation of proton and neutron Fermi energies with temperature and angular momentum is studied. The effect of the variation of nuclear level density with excitation energy on nuclear temperature is verified for different spins.

The effective nucleon mass ${\mathit{M}}_0^{\mathrm{*}}$, incompressibility K, and the third-order derivative K’ of the nuclear saturation curve are studied by using the relativistic mean field model which has both the scalar and the vector mesons self-interactions. The vector meson self-interaction makes it possible to fit K and ${\mathit{M}}_0^{\mathrm{*}}$ with a positive quartic coefficient in the scalar meson potential and to give a soft EOS at high density. The vector meson self-interaction makes K’ smaller, if we fix K(≳200 MeV) and ${\mathit{M}}_0^{\mathrm{*}}$. The Coulomb coefficient ${\mathit{K}}_{\mathit{c}}$ of nucleus incompressibility is also calculated. The parameters of the model are adjusted to fit the empirical values of K and ${\mathit{K}}_{\mathit{c}}$ and, at the same time, to reproduce ${\mathit{M}}_0^{\mathrm{*}}$=0.6M which is consistent with the empirical spin-orbit potential. The obtained EOS with K=300 MeV is successful in accounting for the symmetry properties and is very close to the results of the Dirac-Brueckner-Hartree-Fock calculation.

The nucleon self-energy obtained from the Dirac Brueckner-Hartree-Fock calculation is parametrized by introducing density-dependent coupling constants of isoscalar mesons in the relativistic Hartree-Fock (RHF) approach. The RHF calculations with density-dependent coupling constants not only reproduce the nuclear matter saturation properties, but also provide a good starting point to study finite nuclei properties. The relativistic density-dependent Hartree-Fock (RDHF) approach contains the features of the relativistic G matrix and in the meantime simplifies the calculation. The ground state properties of spherical nuclei calculated in the RDHF are in good agreement with the experimental data. The contribution of isovector mesons π and ρ, especially the contribution of the tensor coupling of ρ meson, are discussed in this paper.

The neutron-skin property of Cs isotopes is studied by the deformed relativistic mean field and spherical nonrelativistic Hartree-Fock theories. We predict a sizable neutron-skin ratio for the isotopes not only near the neutron-drip line, but also far inside, where experimental studies could be done with the present-day experimental facilities. We also show that the surface diffuseness of the neutron distribution increases with the neutron number.

Based on the density functional approach to quantum hadrodynamics a local effective exchange potential for use in nuclear structure calculations beyond the mean-field approximation has been developed. For a conceptual study of the density functional technique the resulting Kohn-Sham single-particle equations have been solved for several spherical nuclei within the linear σ-ω model. A detailed comparison with Hartree-Fock results is given.

Considering one particle motion in a local potential, we derive a set of bounds relating moments of the ground state density to successive excitation energies. We check the validity of these bounds for potentials currently used in nuclear physics. The method is then applied to hypernuclear spectra. We investigate the possibility of determining the local potential experienced by the Λ particle inside the nucleus in a model independent way.

The low-lying collective states of xenon isotopes are studied by means of the boson expansion theory. The microscopic Hamiltonian is comprised of the self-consistent QQ interaction with higher-order (three- and four-body) terms, monopole- and quadrupole-pairing interactions in addition to the spherical limit of the Nilsson Hamiltonian. It is shown that the difficulty of weak strengths of the monopole-pairing interaction in this region, indicated by Rohoziński et al., can be naturally remedied by including the quadrupole-pairing interactions.

The thermal effects on the energies of the isoscalar giant multipole resonances of hot nuclei are discussed and an approximate formula for the energy as a function of temperature is derived via a hydrodynamic theory. The energy difference between the isoscalar giant multipole resonance of a hot nucleus and its ground-state resonance depends on the competition between the volume expansion and the increase of the average kinetic energy per nucleon of hot nuclei, which lower and raise the resonance energy, respectively, and nearly counteract each other in magnitude. The variaiton of the isoscalar giant resonance energy with temperature is very small.

The quasielastic scattering of the exotic nucleus ${}_{}{}^8{}_{}{}^{}\mathrm{B}$ on a ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ target has been studied at an energy of 320 MeV and compared with that of ${}_{}{}^7{}_{}{}^{}\mathrm{Be}$ at the same velocity. The quasielastic scattering of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ + ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ at 20 MeV/nucleon, also performed as a secondary beam experiment, was used to check the data reduction method. The results are interpreted in terms of a semimicroscopic double folding model and coupled-channels calculation. The difference in the total reaction cross section (8%) between ${}_{}{}^8{}_{}{}^{}\mathrm{B}$ and ${}_{}{}^7{}_{}{}^{}\mathrm{Be}$ is consistent with the measured one proton removal cross section and corresponds to an increase in the interaction radius of 4%. The existence of a substantial proton halo in ${}_{}{}^8{}_{}{}^{}\mathrm{B}$ is not supported by the present data.

The differential cross section for the reaction ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$(γ,${\mathrm{\pi }}^{\mathrm{-}}$${)}^{15}$${\mathrm{O}}_{\mathrm{gs}}$ has been measured at a photon energy of 220 MeV. We find a discrepancy between our data and a calculation based on the distorted wave impulse approximation which uses phenomenological 1p-shell wave functions. A second calculation, in which higher-shell configurations are included in the wave functions, fails to correct the discrepancy and is even more at odds with the data.

The yields and recoil properties of the targetlike fragments produced in the interaction of 44, 77, and 95 MeV/nucleon Ar with ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$ have been measured. From these data, the fragment mass distributions, average energies, and the linear momentum transfer leading to their formation have been deduced. The residue yields are large at all energies [790 mb, 790 mb, and 710 mb (±30%) at 44, 77, and 95 MeV/nucleon, respectively] while the average residue energies are low [mean fractional linear momentum transfer (FLMT) is 0.14, 0.12, and 0.13 for the 44, 77, and 95 MeV/nucleon experiments]. Because of the low mean FLMT values associated with the residues, we conclude that, on average, they do not result from fusion-like events. The residue energies and their dependence on fragment mass number agree with predictions of BUU calculations. The substantial survival of the residues of excited, fissionable nuclei is shown to be a result of retardation of fission decay and the broad primary fragment distributions. The intranuclear cascade model is shown to give an incorrect description of the primary fragment properties in these reactions.

Population rates for neutron-unbound states compared to bound states were determined for intermediate mass fragments from ${}_{}{}^{36}{}_{}{}^{}\mathrm{Ar}$+Ag collisions at 35 MeV/nucleon. The population ratios were measured as a function of fragment kinetic energy at angles of 15°, 30°, 45°, and 60°, especially for ${}_{}{}^{12}{}_{}{}^{}\mathrm{B}$ fragments but also for ${}_{}{}^7{}_{}{}^{}\mathrm{Li}$, ${}_{}{}^8{}_{}{}^{}\mathrm{Li}$, ${}_{}{}^{11}{}_{}{}^{}\mathrm{Be}$, and ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ fragments. The results show no major dependence on either the kinetic energy or the emission angle of the fragments. There are signs of a moderate contribution to the dominating statistical decay from nonequilibrium quasi-elastic decay at the smaller angles. The population ratios for the different fragments are consistent with emission from a source of a single temperature which emits complex nuclei at freeze-out. Comparison of the present results with those from a similar experiment, but with ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ projectiles at 35 MeV/nucleon, shows that the population ratios for strongly damped processes are the same for both ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ and ${}_{}{}^{36}{}_{}{}^{}\mathrm{Ar}$ projectiles on Ag.