It might be possible that thermodynamic properties of nuclear matter, such as the caloric curve, could be obtained from heavy-ion reactions. Recent experimental and computational studies of nuclear experiments have obtained contradictory caloric curves for nuclear matter. This work improves on previous theoretical studies by considering the fragmentation produced by collisions, and introducing the methodology needed to identify the fragments, their temperature, energy, and a caloric curve. The main findings are the crucial reduction of energy produced in the promptly emitted particles, the existence of a well-defined fragmentation time, the connection of the temperature of the detected fragments with that at fragmentation time, and the possibility of obtaining the caloric curve from collisions.

We assess the global effect of central and tensor correlations, meson-exchange and isobar currents upon the cross sections for quasielastic ${(e,e}^{\prime }p)$ reactions from nuclei by presenting calculations for the ${}^{16}\mathrm{O}$ target. Four-momenta in the range $0.1<~Q^2<~1\hspace{0.5em}{\mathrm{GeV}}^2$ are addressed. We observe that for $Q^2$ values exceeding $0.2\hspace{0.5em}{\mathrm{GeV}}^2,$ quasielastic conditions and missing momenta below the Fermi momentum, the ground-state correlations and two-body currents do not dramatically alter the magnitude of the ${(e,e}^{\prime }p)$ cross sections as they are obtained in the impulse approximation. Moreover, the deviations from the impulse approximation induced by the two-nucleon photoabsorption mechanisms considered here, exhibit a rather modest $Q^2$ dependence.

We calculate the threshold T-matrices of kaon-nucleon and antikaon-nucleon scattering to one-loop order in SU(3) heavy baryon chiral perturbation theory. To that order the complex-valued isospin-1 $\overline{K}N$ threshold T-matrix can be successfully predicted from the isospin-0 and 1 $\mathrm{KN}$ threshold T-matrices. As expected perturbation theory fails to explain the isospin-0 $\overline{K}N$ threshold T-matrix that is completely dominated by the nearby subthreshold ${\Lambda }^{*}\mathrm{}\left(1405\right)\mathrm{}$ resonance. Cancellations of large terms of second and third chiral order are observed as they seem to be typical for SU(3) baryon chiral perturbation theory calculations. We also give the kaon and eta-loop corrections to the $\pi N$ scattering lengths and we investigate $\pi \Lambda$ scattering to one-loop order. The second order s-wave low-energy constants are all of natural size and do not exceed $1\hspace{0.5em}{\mathrm{GeV}}^{-1}$ in magnitude.

We reconsider the Euler-Lagrange equation for the Skyrme model in the hedgehog ansatz and study the analytical properties of the solitonic solution. In view of the lack of a closed form solution to the problem, we work on approximate analytical solutions. We show that Padé approximants are well suited to continue analytically the asymptotic representation obtained in terms of a power series expansion near the origin, obtaining explicit approximate solutions for the Skyrme equations. We improve the approximations by applying the two-point Padé approximant procedure whereby the exact behavior at spatial infinity is incorporated. An even better convergence to the exact solution is obtained by introducing a modified form for the approximants. The new representations share the same analytical properties with the exact solution at both small and large values of the radial variable r.

The lowest excited $K=0\mathrm{}$ bands in ${}^{238}\mathrm{U}$ have been studied by internal conversion electron spectroscopy following Coulomb excitation with $\alpha$ particles at 19 MeV. Strong $E0\mathrm{}$ enhancement was found for transitions between the $2^{+}$ members of the $0_2^{+},$ $0_3^{+}$ bands and of the ground state rotational band, and $E0\mathrm{}$ strength values of 0.0099(18) and 0.175(26) were determined. Based on our more accurate energy value of the $0_3^{+}$ state, 997.23(24) keV, the moments of inertia for the excited $K=0\mathrm{}$ bands were studied.

We give a description of the binary cold fission process of ${}^{252}\mathrm{Cf}$ within the stationary scattering formalism. The nuclear interaction is given by a double folding procedure using M3Y forces plus a repulsive contact potential. For the experimental Q value we find several resonant states of the binary system, depending on the nuclear repulsive strength. We predict a strong dependence of decay widths upon the internal structure of the considered resonance state. Therefore the measured yields of the two fragments with given angular momenta in coincidence are able to give the information concerning the internal molecular dynamics.

A systematic analysis of the moments of the fragment size distribution has been carried out for the multifragmentation of $1A\mathrm{GeV}$ Au, La, and Kr on carbon. The breakup of Au and La is consistent with a continuous thermal phase transition. The data indicate that the excitation energy per nucleon and isotopic temperature at the critical point decrease with increasing system size. This trend is attributed primarily to the increasing Coulomb energy with finite size effects playing a smaller role.

Using a relativistic transport model for heavy ion collisions at energies that are below the threshold for kaon and antikaon production in nucleon-nucleon collisions, we study how their abundances approach the canonical equilibrium during the collisions. We find that kaons are far from chemical equilibrium at the initial and high density stage, and they approach equilibrium only during the expansion stage of the collisions when their production rate is small and becomes comparable to their annihilation rate. In contrast, antikaons approach chemical equilibrium much earlier but eventually fall out of equilibrium again as a result of their large annihilation cross sections in nuclear matter.

The elastic backward proton-deuteron scattering is analyzed within a covariant approach based on the invariant expansion of the reaction amplitude. The relativistic invariant equations for all the polarization observables are presented. Within the impulse approximation the relation of the tensor analyzing power $T_{20}$ and the polarization transfer ${\kappa }_0$ to the P-wave components of the deuteron wave function is found. Comparison of the theoretical calculations with the experimental data is presented. Experimental verification of the reaction mechanism by constructing some combinations of different observables is suggested.

Excitation energy spectra of ${}_{\mathrm{\Lambda }}^{89}\mathrm{Y},$ ${}_{\mathrm{\Lambda }}^{51}\mathrm{V},$ and ${}_{\mathrm{\Lambda }}^{12}\mathrm{C}$ have been measured via the $\left({\pi }^{+}{,K}^{+}\right)$ reaction by using the SKS spectrometer at the K6 beam line in the KEK 12-GeV Proton Synchrotron. In the ${}_{\mathrm{\Lambda }}^{89}\mathrm{Y}$ spectrum, obtained with an energy resolution of 1.65 MeV (FWHM) and in the highest statistics so far, we have succeeded in clearly observing a characteristic fine structure in heavy Λ hypernuclear systems and precisely obtaining a series of Λ single-particle energies in the very wide excitation energy range of more than 20 MeV, for the first time. Also in the ${}_{\mathrm{\Lambda }}^{51}\mathrm{V}$ spectrum, a similar structure to that of ${}_{\mathrm{\Lambda }}^{89}\mathrm{Y}$ was observed. In the ${}_{\mathrm{\Lambda }}^{12}\mathrm{C}$ spectrum, new core-excited states were clearly resolved thanks to the best energy resolution of 1.45 MeV so far achieved by using the SKS spectrometer.

The near proton drip-line nucleus ${}^{126}\mathrm{Pr}$ was studied via in-beam $\gamma$-ray spectroscopy using the ${}^{40}\mathrm{Ca}{+}^{92}\mathrm{Mo}$ reaction at 190 MeV. We observed for the first time excited states above the known isomer in this nucleus, up to spin $31ħ.$ The observed band is assigned to a $\pi h_{11/2}\otimes \nu h_{11/2}$ configuration and is discussed in the framework of the interacting boson-fermion-fermion model. The calculations and the experimental information suggest a spin $8^{+}$ for the lowest observed state. With such a spin assignment the moment of inertia of ${}^{126}\mathrm{Pr}\mathrm{}$ gets larger than in the heavier Pr isotopes, suggesting a sudden change in deformation close to the proton drip line.

The propagation of the isoscalar and isovector sound modes in a hot nuclear matter is considered. The approach is based on the collisional kinetic theory and takes into account the temperature and memory effects. It is shown that the sound velocity and the attenuation coefficient are significantly influenced by the Fermi surface distortion (FSD). The corresponding influence is much stronger for the isoscalar mode than for the isovector one. The memory effects cause a nonmonotonous behavior of the attenuation coefficient as a function of the relaxation time leading to a zero-to-first sound transition with increasing temperature. The mixing of both the isoscalar and the isovector sound modes in an asymmetric nuclear matter is evaluated. The condition for the bulk instability and the instability growth rate in the presence of the memory effects is studied. It is shown that both the FSD and the relaxation processes lead to a shift of the maximum of the instability growth rate to the longer-wavelength region.

Experimental data for ${}^6\mathrm{He}{+}^1\mathrm{H}$ elastic scattering and the two-neutron transfer reaction, measured recently at the Joint Institute for Nuclear Research in Dubna, Russia, were analyzed by coupled channels calculations using a dineutron model of ${}^6\mathrm{He}.$ The results of the analysis reveal that all the processes induced by ${}^6\mathrm{He}$ on a hydrogen target are coupled. This analysis shows that the couplings to the ${}^6\mathrm{He}\to \alpha +2n$ breakup channels can be included in a simple optical model calculation by means of a polarization potential that is repulsive and whose strength is about 25% of the single-folding potential. Predictions for the ${p+}^6\mathrm{He}$ inelastic scattering to the $2^{+}$ resonance are made. A good description of the two-neutron transfer reaction data is obtained when the triton transfer process is coherently added to the dineutron transfer. The spectroscopic amplitude of the $t+t$ component of the ${}^6\mathrm{He}$ ground-state wave function is found to have the opposite sign to that of $\alpha +2n$ with a magnitude close to that predicted by a microscopic four-cluster model of ${}^6\mathrm{He}.$

Subthreshold events (pion production, for instance, at energies $E<\mathrm{}{m}_{\pi })$ in heavy-ion collisions are treated as rare cluster-cluster collision events. On kinematical grounds such events are forbidden in free nucleon-nucleon and even nucleon-nucleus collisions. We show, by using effective mass clustering arguments, that the associated distribution $P_c\mathrm{}\left(n\right),$ when the pion trigger is present, and the unconstrained distribution $P\left(n\right),$ when there is no pion trigger, are related by the universal relation $P_c{\mathrm{}\left(n\right)=(n}^2/〈n^2〉\left)P\right(n).$ This relation, and in particular an improved version taking into account the number of clustering nucleons, is in fair agreement with data. Moreover, it allows information to be extracted from the multiplicity data on the number of nucleons involved in subthreshold meson production processes.

We consider the $J/\Psi$ suppression at a high energy heavy ion collision. An ideal gas of massive hadrons in thermal and chemical equilibrium is formed in the central region. The finite-size gas expands longitudinally in accordance with Bjorken law. The transverse expansion in a form of the rarefaction wave is taken into account. We show that $J/\Psi$ suppression in such an environment, when combined with the disintegration in nuclear matter, gives correct evaluation of NA38 and NA50 data in a broad range of initial energy densities.

The main properties (strength function, energy-dependent transition density, branching ratios for direct nucleon decay) of the isoscalar giant dipole resonance in several medium-heavy mass spherical nuclei are described within a continuum random-phase approximation approach, taking into account the smearing effect. All model parameters used in the calculations are taken from independent data. The calculation results are compared with available experimental data.

Magnetic transition strengths in ${}^{134}\mathrm{Ba}$ are discussed within the framework of the nucleon-pair shell model (NPSM) truncated to the $\mathrm{SD}$ subspace. The S and D pairs are determined, respectively, by a variational method and a proton-neutron TDA approximation. The $M1\mathrm{}$ and $M3\mathrm{}$ transition strengths are found to be consistent with results from the proton-neutron interacting boson model calculations. The results confirm that the collective magnetic properties of ${}^{134}\mathrm{Ba}$ are primarily due to the orbital motion of nucleons.

Coulomb effects in the neutron-deuteron and proton-deuteron polarization-transfer coefficients $K_y^{y^{\prime }},$ $K_z^{x^{\prime }},$ $K_y^{x^{\prime }{x}^{\prime }-y^{\prime }{y}^{\prime }},$ and $K_y^{z^{\prime }{z}^{\prime }}$ are studied at energies above the deuteron breakup threshold. Theoretical predictions for these observables are evaluated in the framework of the Kohn variational principle using correlated basis functions to expand the three-nucleon scattering wave function. The two-nucleon Argonne $v_{18}$ and the three-nucleon Urbana IX potentials are considered. In the proton-deuteron case, the Coulomb interaction between the two protons is included explicitly and the results are compared to the experimental data available at $E_{\mathrm{lab}}=10,19,22.7\mathrm{}\hspace{0.5em}\mathrm{MeV}.$ In the neutron-deuteron case, a comparison to a recent measurement of $K_y^{y^{\prime }}$ by Hempen et al. at $E_{\mathrm{lab}}=19\mathrm{}\hspace{0.5em}\mathrm{MeV}$ evidences a contribution of the calculated Coulomb effects opposite to those extracted from the experiment.

The neutron charge form factor $G_{\mathrm{En}}\mathrm{}\left(q\right)\mathrm{}$ is determined from an analysis of the deuteron quadrupole form factor $F_{C2\mathrm{}}\mathrm{}\left(q\right)\mathrm{}$ data. Recent calculations, based on a variety of different model interactions and currents, indicate that the contributions associated with the uncertain two-body operators of shorter range are relatively small for $F_{C2\mathrm{}}\mathrm{}\left(q\right),$ even at large momentum transfer q. Hence, $G_{\mathrm{En}}\mathrm{}\left(q\right)\mathrm{}$ can be extracted from $F_{C2\mathrm{}}\mathrm{}\left(q\right)\mathrm{}$ at large $q^2$ without undue systematic uncertainties from theory.

High spin states have been studied in the nucleus ${}^{100}\mathrm{Pd}$ with the aim of investigating the novel phenomenon of “antimagnetic rotation.” A cascade of four “rotational-band-like” transitions is proposed as corresponding to antimagnetic rotation, based on the observed spectroscopic properties and a comparison with calculations in the configuration-dependent cranked Nilsson-Strutinsky formalism.