The multifragmentation of quasiprojectiles was studied in the reactions of a ${}^{28}\mathrm{Si}$ beam with ${}^{112}\mathrm{Sn}$ and ${}^{124}\mathrm{Sn}$ targets at projectile energies of 30 and 50 MeV/nucleon. The quasiprojectile observables were reconstructed using isotopically identified charged particles with $Z_f<~5$ detected at forward angles. The nucleon exchange between projectile and target was investigated using the isospin and the excitation energy of the reconstructed quasiprojectile. For events with total reconstructed charge equal to the charge of the beam ${(Z}_{\mathrm{tot}}=14),$ the influence of the beam energy and target isospin on the neutron transfer was studied in detail. Simulations were carried out employing a model of deep inelastic transfer, a statistical model of multifragmentation, and a software replica of the FAUST detector array. The concept of deep inelastic transfer provides a good description of the production of highly excited quasiprojectiles. The isospin and excitation energy of the quasiprojectile were described with good overall agreement. The fragment multiplicity, charge and isospin were reproduced satisfactorily. The range of contributing impact parameters was determined using a backtracing procedure.

A Newton-Sabatier fixed energy inversion scheme has been used to determine complex, energy dependent local potentials that are phase equivalent to inherently nonlocal $p{-}^{12}\mathrm{C}$ ones and for a variety of energies to pion threshold. Those energy dependent local potentials then have been recast in the form of nonlocal Frahn-Lemmer interactions.

Elastic and inelastic scattering of 800 MeV protons from the axially deformed nucleus ${}^{26}\mathrm{Mg}$ is analyzed using optical potentials obtained from the relativistic impulse approximation (RIA) in Dirac coupled channel formalism. A rotational collective model is used to obtain the transition optical potentials for the low-lying excited states of the ground-state rotational band. The theoretical results agree with the experimental data for the elastic and the $2^{+}$ state, and reproduce the $4^{+}$ excited state reasonably well. In order to check these RIA results we perform Dirac phenomenological (DP) analysis of the data and obtain the best fit Lorentz scalar and vector optical potentials. RIA and DP optical potentials are compared with those of a similar treatment for 800 MeV protons scattering from ${}^{24}\mathrm{Mg}.$

$\mathrm{D}\mathrm{o}\mathrm{u}\mathrm{b}\mathrm{l}\mathrm{e}-\gamma$ vibrations in deformed nuclei are analyzed in the context of the interacting boson model. A simple extension of the original version of the model towards higher-order interactions is required to explain the observed anharmonicities of nuclear vibrations. The influence of three- and four-body interactions on the moments of inertia of ground and $\gamma$ bands, and on the relative position of $\mathrm{s}\mathrm{i}\mathrm{n}\mathrm{g}\mathrm{l}\mathrm{e}-\gamma$ and $\mathrm{d}\mathrm{o}\mathrm{u}\mathrm{b}\mathrm{l}\mathrm{e}-\gamma$ bands is studied in detail. As an example of a realistic calculation, spectra and transitions of the highly $\gamma -\mathrm{a}\mathrm{n}\mathrm{h}\mathrm{a}\mathrm{r}\mathrm{m}\mathrm{o}\mathrm{n}\mathrm{i}\mathrm{c}$ nuclei ${}^{164}\mathrm{Dy},$ ${}^{166}\mathrm{Er},$ and ${}^{168}\mathrm{Er}$ are interpreted in this approach.

We perform a systematic study of in-plane and out-of-plane proton and neutron flow from nucleus-nucleus collisions within the Boltzmann-Uehling-Uhlenbeck transport approach, employing different parameter sets for the mean-field potentials that can be characterized by the nuclear incompressibility and the stiffness of the momentum-dependent potential. We find that a simultaneous description of the experimental data from the BEVALAC and the SIS on both the nucleon squeeze-out $v_2$ and the in-plane flow F at beam energies $E_{\mathrm{lab}}=0.15\mathrm{}–2\hspace{0.5em}A\mathrm{}\mathrm{GeV}$ requires a mean field with strong momentum dependence, i.e., an effective Landau mass $m^{*}\simeq {0.68m}_0$ at normal nuclear matter density ${\rho }_0=0.17\mathrm{}\hspace{0.5em}{\mathrm{fm}}^{-3},$ where $m_0=0.938\mathrm{}\hspace{0.5em}\mathrm{GeV}$ is the bare nucleon mass. Some experimental data on the squeeze-out require an even stiffer momentum dependence ${(m}^{*}\approx {0.62m}_0).\mathrm{}$ All systems investigated are found to be compatible with $m^{*}{/m}_0=0.65\mathrm{}\pm \mathrm{0.03.}$

Kinematically complete events have been studied for the reactions $d\overrightarrow{p}\mathrm{dp}{\pi }^0$ and $d\overrightarrow{p}\mathrm{dn}{\pi }^{+}$ at projectile energies between 437 and 559 MeV. The measurement covers a range of pion momenta $\eta {=p}_{\pi ,\mathrm{c}.\mathrm{m}.\mathrm{}}^{\max }{/m}_{\pi }c$ from near the production threshold $(\eta =0.32)$ to $\eta =0.86\mathrm{}$ close to the $N\overrightarrow{N}\mathrm{NN}\pi$ threshold. The measurements were performed at the CELSIUS storage ring with the PROMICE/WASA setup. Angular and spectral distributions of the charged ejectiles as well as total cross sections are decomposed into the fractions that can be attributed to a quasifree $N\overrightarrow{N}d\pi$ process with a spectator nucleon, and to a process involving all three nucleons. The quasifree contribution increases with energy and dominates from the $N\overrightarrow{N}\mathrm{NN}\pi$ threshold on. The results are compared to calculations with a spectator model with and without $\mathrm{dp}$ final state interactions.

In bombardments of ${}^{244}\mathrm{Pu}$ targets with 114- and 120-MeV ${}^{22}\mathrm{Ne}$ projectiles we detected 69 $\alpha -\alpha$ correlations linking $\alpha$ decays of ${}^{261}\mathrm{Rf}$ and ${}^{257}\mathrm{No}.$ We observed one $\alpha$ peak with $E_{\alpha }=8.30\mathrm{}\pm 0.06$ MeV for ${}^{261}\mathrm{Rf}$ and peaks with α-particle energies 8.07–8.40 MeV for ${}^{257}\mathrm{No}.$ The half-life of ${}^{257}\mathrm{No}$ was measured to be $25\pm 3$ s. No correlations were found between $\alpha$ decays and subsequent spontaneous fission events, from which we calculated an upper limit of 1.5% for the fission branch of ${}^{257}\mathrm{No}$ and estimated an upper limit of 3% for the α-decay branch of ${}^{262}\mathrm{Rf}.$ The cross section of the ${}^{244}\mathrm{Pu}{(}^{22}\mathrm{Ne}{,5n)}^{261}\mathrm{Rf}$ reaction was measured to be about 4 nb at both ${}^{22}\mathrm{Ne}$ energies used. We also report on some results from ${}^{242}\mathrm{Pu}{+}^{22}\mathrm{Ne}$ and ${}^{238}\mathrm{U}{+}^{26}\mathrm{Mg}$ bombardments.

We determine properties of single and multilambda hypernuclei in the Skyrme-Hartree-Fock formalism, which is supplemented by a microscopic in-medium lambda-nucleon interaction derived from self-consistent Brueckner-Hartree-Fock calculations with the Nijmegen soft-core hyperon-nucleon potential. Existing data for single-lambda hypernuclei are well reproduced, apart from a slight underbinding of heavy nuclei. In multilambda hypernuclei, we study in particular the effects of the modification of the nuclear core due to the presence of the hyperons.

The underlying mechanism involved in the production of very neutron-rich nuclides using projectile fragmentation is studied with an abrasion-ablation (AA) model. The AA model suggests that very neutron-rich nuclides are produced by removing nearly all the required protons in the nonequilibrium abrasion stage, with minimal evaporation of neutrons in the ablation stage—“cold fragmentation.” Furthermore, the production of the most neutron-rich nuclei from a fixed projectile relies heavily on the neutron fluctuations in the ablation stage. The production of the nuclides closest to the neutron drip line using neutron-rich unstable beams is examined.

We extend a modified Newton-Sabatier method for the solution of the fixed energy, coupled channels, inverse scattering problem to deal with a set of cluster transfer reactions. The method is tested by using analytic model potentials for the transfer reaction ${}^{16}\mathrm{O}(\alpha {,}^8\mathrm{Be}{)}^{12}\mathrm{C}.$ For low energy scattering we show that inclusion of S matrices for nonphysical, noninteger angular momenta are required to find stable solutions. The possibility of application to actual experimental data is discussed.

The astrophysical S factor of the ${}^7\mathrm{Be}(p,\gamma {)}^8\mathrm{B}$ radiative capture reaction is analyzed at zero energy in a simplified potential model where the scattering wave function and its energy derivative at zero energy are replaced by their asymptotic expressions. A positive (negative) scattering length in the initial s wave reduces (increases) the value of $S\left(0\right).$ The ratio $S^{\prime }\mathrm{}\left(0\right)/S\left(0\right)\mathrm{}$ is much more sensitive to the scattering length than $S\left(0\right).$ The effective range of the initial wave is found to play a negligible role. Existing models suggest a negative value for the scattering length, but not large enough to lead to important corrections.

The electromagnetic transitions to various low-lying excited states of ${}^{16}\mathrm{O},$ ${}^{48}\mathrm{Ca},$ and ${}^{208}\mathrm{Pb}$ are calculated within a model which considers the short-range correlations. In general the effects of the correlations are small and do not explain the required quenching to describe the data.

In an earlier work we introduced a covariant model of quarkonium-glueball mixing and calculated the wave functions of the various mixed scalar-isoscalar $\mathrm{s}\mathrm{t}\mathrm{a}\mathrm{t}\mathrm{e}\mathrm{s}:\hspace{1em}{f}_0\mathrm{}\left(980\right),$ $f_0\mathrm{}\left(1370\right),$ $f_0\mathrm{}\left(1500\right),$ and $f_0\mathrm{}\left(1770\right).$ In the present work we introduce the widths of these states and describe glueball mixing with the $f_0(400\mathrm{}–1200)$ resonance using a perturbative scheme. Part of our motivation lies in the recent work of Narison who used QCD sum-rule techniques to study the distribution of glueball strength among scalar, pseudoscalar, and tensor mesons. We find little change of our previous results with little strength in the energy region below the $f_0\mathrm{}\left(980\right)\mathrm{}$ resonance. Our result is in contrast to the result of the QCD sum-rule analysis that suggests that there is a good deal of glueball strength in the region near or below 1 GeV.

Measurements at 19 beam kinetic energies between 1795 and 2235 MeV are reported for the $\mathrm{pp}$ elastic scattering spin correlation parameter $A_{00nn}{=A}_{\mathrm{NN}}{=C}_{\mathrm{NN}}.$ The c.m. angular range is typically 60–100°. The measurements were performed at Saturne II with a vertically polarized beam and target (transverse to the beam direction and scattering plane), a magnetic spectrometer and a recoil detector, both instrumented with multiwire proportional chambers, and beam polarimeters. These results are compared to previous data from Saturne II and elsewhere.

We discuss different aspects which might influence temperatures deduced from experimental isotopic yields in the multifragmentation process. It is shown that fluctuations due to the finite size of the system and distortions due to the decay of hot primary fragments conspire to blur the temperature determination in multifragmentation reactions. These facts suggest that caloric curves obtained through isotope thermometers, which were taken as evidence for a first-order phase transition in nuclear matter, should be investigated very carefully.

A basic assumption which underpins recent applications of eikonal few-body models to nuclear scattering and nuclear reactions is that of the addition of the constituent scattering phases. We investigate the accuracy of this assumption in the case of the elastic scattering of ${}^8\mathrm{He},$ treated as a five-constituent $(\alpha +4n)$ system, from a light target nucleus at energies of 10’s of MeV/nucleon. To do so we calculate Feshbach’s correlated scattering or overlapping potential contributions to the eikonal model phase shifts in this many-body case. We find that even for ${}^8\mathrm{He},$ with ten contributing pair-wise potential overlaps, these terms introduce corrections that are small in comparison with available experimental precision and also compared to those phase additive noneikonal corrections which arise from the use of an improved description of the phase shifts for each of the constituent-target subsystems within the few-body model.

Kaon production in pion-nucleon collisions in nuclear matter is studied in the resonance model. To evaluate the in-medium modification of the reaction amplitude as a function of the baryonic density we introduce relativistic, mean-field potentials for the initial, final, and intermediate mesonic and baryonic states. These vector and scalar potentials were calculated using the quark-meson coupling model. The in-medium kaon production cross sections in pion-nucleon interactions for reaction channels with $\Lambda$ and $\Sigma$ hyperons in the final state were calculated at the baryonic densities appropriate to relativistic heavy ion collisions. Contrary to earlier work which has not allowed for the change of the cross section in-medium, we find that the data for kaon production are consistent with a repulsive $K^{+}$-nucleus potential.

A practical quantum-field treatment is developed for systems endowed with an effective mass function depending on both space and time and a schematic application illustrates the quantitative importance of quantum fluctuations in the dynamics of disoriented chiral condensates.

Neutrino interactions with lead produce neutrons in numbers that depend on neutrino energy and type. A detector based on lead perchlorate, for example, would be able to measure the energy deposited by electrons and gammas in coincidence with the number of neutrons produced. Sorting the electron energy spectra by the number of coincident neutrons permits the identification of the neutrino type that induced the reaction. This separation allows an analysis which can determine the temperatures of ${\nu }_e$ and ${\overline{\nu }}_e$ from a supernova in one experiment. The neutrino reaction signatures of lead perchlorate, and the fundamentals of using this material as a neutrino detector, are described.

The level structure of ${}^{225}\mathrm{Ra},$ produced in $\alpha$ decay of ${}^{229}\mathrm{Th},$ was studied by $\gamma$-ray spectroscopy. The sources were continuously purified from daughters with ion-exchange chromatographic separation methods. Energies and intensities of 174 $\gamma$ rays were accurately measured with HPGe detectors. About 100 $\gamma$ rays were reported for the first time, especially in the 300–700 keV energy range. A ${}^{225}\mathrm{Ra}$ level scheme was proposed, accounting for about 200 transitions among 45 excited states. The level structure was interpreted in the framework of reflection-asymmetric structures with parity doublet bands. The model was shown to be in satisfactory agreement with experimental data.