Total reaction cross sections are predicted for proton scattering from various nuclei. A simple functional form has been used that reproduces them for the scattering from (15) nuclei spanning the mass range from ${}^9\mathrm{Be}$ to ${}^{238}\mathrm{U}$ and for proton energies 10–300 MeV.

Elastic scattering differential cross sections were measured for the ${}^{28}\mathrm{Si}{+}^{58}\mathrm{Ni}$ system at sub-barrier energies. The corresponding nuclear potential was compared with earlier results of systems like ${A+}^{58}\mathrm{Ni}.$ The present data also allowed the determination of the ${}^{28}\mathrm{Si}$ nuclear density through an unfolding method. The experimentally extracted ${}^{28}\mathrm{Si}$ density values are compared with those previously obtained for the ${}^{4,6}\mathrm{He},$ ${}^{12}\mathrm{C},$ ${}^{16,18}\mathrm{O}$ nuclei. We present a critical discussion of the absolute precision obtained for the density parameters extracted from the data analyses.

A simple model for diffusion of a particle with initial velocity coupled to a non-Ohmic environment over a barrier is proposed. An exact expression for the passing probability of the particle over a parabolic potential barrier is obtained. It is shown that in the case of subdiffusion, more than half of the particles cannot overcome the barrier, no matter what the initial velocity is. However, in the case of superdiffusion, a minimum critical velocity needed for passing over the barrier is found, which can lead to a strong friction and make the passing probability increase with kinetic energy, but still slower than in the case of normal diffusion. Effects of quantum diffusion and zero point fluctuation are also discussed. The model is applied to solve a long-standing problem in nuclear fusion reactions, though the mechanism found in this study can have a rather broad application.

Analytical solutions of dispersion relations in the nucleon-nucleus optical model have been found for both volume and surface potentials. For the energy dependence a standard Brown-Rho function has been assumed for both the volume and surface imaginary contributions multiplied in this later case by a decreasing exponential function. The solutions are valid for any even value of the powers appearing in these functional forms.

The dispersion relation of $\rho$ meson in both timelike and spacelike regimes in a hot and dense nuclear medium is analyzed and compared with $\sigma$ meson based on the quantum hadrodynamics model. The pole and screening masses of $\rho$ and $\sigma$ are discussed. The behavior of screening mass of $\rho$ is different from that of $\sigma$ due to different Dirac- and Fermi-sea contributions at finite temperature and density.

Contributions of three-nucleon forces (3NF) to proton-deuteron scattering observables at energies below the deuteron breakup threshold are studied by solving the Faddeev equation that includes the Coulomb interaction. At $E_p=3.0\mathrm{}\mathrm{MeV},$ we find that the central part of a two-pion exchange 3NF removes the discrepancy between measured cross sections and the calculated ones by two-nucleon forces, and improves the agreement with $T_{22}$ experimental data. However, the tensor part of the 3NF fails in reproducing data of the analyzing power $T_{21}$ by giving worse agreement between the measured and the calculated. Detailed examinations of scattering amplitudes suggest that a P-wave contribution in spin-quartet tensor amplitudes has unsuitable sign for reproducing the $T_{21}$ data.

The ${}^1{S}_0$ superfluidity of neutron matter is studied in the framework of the generalized Gorkov equation. Vertex corrections to the pairing interaction and the self-energy corrections are introduced and approximated on the same footing in the gap equation. A suppression of the pairing gap by more than $50\%$ with respect to the BCS prediction is found, which deeply changes the scenario for the dynamical and thermal evolution of neutron stars.

We have analyzed four sets of α-transfer data leading to three $L=3\mathrm{}$ states in ${}^{19}\mathrm{F}$ and extracted absolute α-particle spectroscopic factors. A comparison of the results aids in evaluating reliability of these quantities, which enter calculations of stellar burning.

$\beta$ decays of on-line mass-separated neutron-rich ${}^{118}\mathrm{Ag}$ and ${}^{120}\mathrm{Ag}$ isotopes have been studied by using $\beta -\gamma$ and $\gamma -\gamma$ coincidence spectroscopy. Extended decay schemes to the ${}^{118,120}\mathrm{Cd}$ daughter nuclei have been constructed. The three-phonon quintuplet in ${}^{118}\mathrm{Cd}$ is completed by including a new level at 2023.0 keV, which is tentatively assigned the spin and parity of $2_4^{+}.$ The intruder band in ${}^{118}\mathrm{Cd}$ is proposed up to the $4^{+}$ level at 2322.4 keV. The measured $\beta$-decay half-life for the high-spin isomer of ${}^{120}\mathrm{Ag}$ is $0.40\pm 0.03\mathrm{s}.$ Candidates for the three-phonon states, as well as the lowest members of the intruder band in ${}^{120}\mathrm{Cd},$ are also presented. These data support the coexistence of quadrupole anharmonic vibration and proton particle-hole intruder excitations in ${}^{118,120}\mathrm{Cd}.$

The level structures of ${}^{106,108,110,112}\mathrm{Rh}$ have been studied in the fission of the compound system formed in three different heavy-ion induced reactions. Sequences of five transitions, together with weak crossover transitions, have been assigned to each isotope based on coincidences with known transitions in the complementary fragments. Comparison with the lighter odd-odd Rh isotopes supports assignment of these sequences as the yrast bands built on the $\pi g_{9/2}\otimes \nu h_{11/2}$ configuration.

The emission of hard real photons from thermalized expanding hadronic matter is dominated by the initial high-temperature expansion phase. Therefore, a measurement of photon emission in ultrarelativistic heavy-ion collisions provides valuable insights into the early conditions realized in such a collision. In particular, the initial temperature of the expanding fireball or equivalently the equilibration time of the strongly interacting matter are of great interest. An accurate determination of these quantities could help to answer the question whether or not partonic matter (the quark-gluon plasma) is created in such collisions. In this work, we investigate the emission of real photons using a model that is based on the thermodynamics of QCD matter and which has been shown to reproduce a large variety of other observables. With the fireball evolution fixed beforehand, we are able to extract limits for the equilibration time by a comparison with photon emission data measured by WA98.

The dynamical model of pion electroproduction developed by Sato and Lee [Phys. Rev. C $63,$ 055201 (2001)] has been extended to investigate the weak pion production reactions. With the conserved vector current hypothesis, the weak vector currents are constructed from electromagnetic currents by isospin rotations. Guided by the effective chiral Lagrangian method and using the unitary transformation method developed previously, the weak axial vector currents for $\pi$ production are constructed with no adjustable parameters. In particular, the $N-\Delta$ transitions at $Q^2\to 0$ are calculated from the constituent quark model and their $Q^2$ dependence is assumed to be identical to that determined in the study of pion electroproduction. The main feature of our approach is to renormalize these bare $N-\Delta$ form factors with the dynamical pion cloud effects originating from the nonresonant $\pi$ production mechanisms. The predicted cross sections of neutrino-induced pion production reactions, $N({\nu }_{\mu },{\mu }^{-}\pi )N,$ are in good agreement with the existing data. We show that the renormalized (dressed) axial $N-\Delta$ form factor contains large dynamical pion cloud effects and these renormalization effects are crucial in getting agreement with the data. We conclude that the $N-\Delta$ transitions predicted by the constituent quark model are consistent with the existing neutrino-induced pion production data in the $\Delta$ region, contrary to the previous observations. This is consistent with our previous findings in the study of pion electroproduction reactions. However, more extensive and precise data of neutrino-induced pion production reactions are needed to further test our model and to pin down the $Q^2$ dependence of the axial vector $N-\Delta$ transition form factor.

The yrast level schemes of three neutron deficient nuclei with mass $A\approx 95$ have been studied with the reaction ${}^{58}\mathrm{Ni}{+}^{40}\mathrm{Ca}$ at 135 MeV, using the GASP $\gamma$-ray array, the ISIS silicon ball, and the n-ring neutron detector. Excited levels, including a ${(23/2\mathrm{}}^{+})$ spin-gap isomer, are reported for the first time in the heaviest $N=Z+1\mathrm{}$ nucleus experimentally investigated, ${}^{95}\mathrm{Ag}.$ In ${}^{95}\mathrm{Pd},$ the yrast line above the ground state has been observed and connected to states above the known isomeric level ${21/2}^{+},$ showing for the first time that this is indeed a spin-gap isomer. In ${}^{94}\mathrm{Pd},$ the 95.6-keV isomeric transition was confirmed, and its $E2\mathrm{}$ character was firmly established. The experimental observations are compared with current shell-model calculations.

Within the framework of the relativistic distorted wave impulse approximation (DWIA), we investigate the sensitivity of the analyzing power—for exclusive proton knockout from the ${3s}_{1/2},$ ${2d}_{3/2},$ and ${2d}_{5/2}$ states in ${}^{208}\mathrm{Pb},$ at an incident laboratory kinetic energy of 202 MeV, and for coincident coplanar scattering angles $(28.0\mathrm{}°,-54.6°)$ —to different distorting optical potentials, finite-range (FR) versus zero-range (ZR) approximations to the DWIA, as well as medium-modified coupling constants and meson masses. Results are also compared to the nonrelativistic DWIA predictions based on the Schrödinger equation. Whereas the nonrelativistic model fails severely, both ZR and FR relativistic DWIA models provide an excellent description of the data. For the FR predictions, it is necessary to invoke a 20% reduction of $\sigma -\mathrm{n}\mathrm{u}\mathrm{c}\mathrm{l}\mathrm{e}\mathrm{o}\mathrm{n}$ and $\omega$-nucleon coupling constants as well as for $\sigma -,$ $\rho -,$ and $\omega -\mathrm{m}\mathrm{e}\mathrm{s}\mathrm{o}\mathrm{n}$ masses, by the nuclear medium. On the other hand, the ZR predictions suggest that the strong interaction in the nuclear medium is adequately represented by the free nucleon-nucleon interaction associated with the impulse approximation. We also demonstrate that, although the analyzing power is relatively insensitive to the use of different relativistic global optical potential parameter sets, the prominent oscillatory behavior of this observable is largely attributed to distortion of the scattering wave functions relative to their plane wave values.

A black-disk model combined with accurate matter densities has been used for an investigation of reaction cross sections for ${}^3\mathrm{He},$ ${}^4\mathrm{He},$ and ${}^{12}\mathrm{C}$ projectiles. A simple relation is derived between the energy dependence of the reaction cross sections and the strength of the nucleon-nucleon interaction. A comparison is also made of the reaction cross sections for ${}^3\mathrm{He}$ and ${}^4\mathrm{He}$ for six different nuclei, ${}^{12}\mathrm{C},$ ${}^{16}\mathrm{O},$ ${}^{40}\mathrm{Ca},$ ${}^{58,60}\mathrm{Ni},$ and ${}^{208}\mathrm{Pb}.$

The ground state properties of odd-$Z$ superheavy nuclei in the mass range of $Z=97\mathrm{}–115$ and $N=140\mathrm{}–190$ are systematically investigated in deformed relativistic mean-field (RMF) theory. Special emphasis is placed on nuclear shell effect around $N=184.\mathrm{}$ Calculations clearly show that the RMF model can reliably reproduce the data of binding energy and $\alpha$ decay energy of known nuclei and can also be used to predict the binding energy of unknown nuclei. It is found that deformation plays an important role for many superheavy nuclei. For $N=184\mathrm{}$ isotones, the lighter ones are approximately spherical but the heavier ones are deformed. The $\alpha$-decay energies of $N=184\mathrm{}$ isotones are lower than those of neighboring nuclei in some cases and higher in other cases. This demonstrates that there is a complicated structural behavior for $N=184\mathrm{}$ isotones.

For a description of elastic and inelastic $\alpha -p$ scattering exciting $N^{*}$ resonances optical potentials and transition potentials were derived by folding nucleon and nucleus mass densities with a variable range effective interaction. For elastic $\alpha -p$ scattering in forward direction, a reasonable description of essentially all data has been obtained from low energies up to the GeV region. Also, $\alpha$ scattering from ${}^4\mathrm{He}$ and ${}^{12}\mathrm{C}$ is quite well described with potentials, which indicate that the used folding method is a valid approach for the systems in question. The strong energy dependence of the deduced potentials can be accounted for by a sum of scalar and vector meson-exchange potentials and a soft Pomeron-exchange contribution. The scalar meson-exchange potential falls off rapidly with energy and has a large radius in agreement with theoretical predictions. Consistent with the flavor SU(3) quark model, the vector-meson coupling is rather weak in the central potential, but is strong in the spin-orbit potential, for which a soft Pomeron contribution is negligible. The differences between the deduced $\alpha -p$ and nucleon-nucleon $\mathrm{}\left(\mathrm{NN}\right)\mathrm{}$ potentials are understood; further, an excellent description of the energy dependence of the s-wave $\mathrm{NN}$ amplitudes is obtained in the folding model framework. Distorted wave Born approximation calculations for inelastic $\alpha -p$ scattering show a t-dependence of the $L=0\mathrm{}$ cross section consistent with empirical form factors. Absolute yields for excitation of the resonances $P_{11}\mathrm{}\left(1440\right),$ $D_{13}\mathrm{}\left(1520\right)\mathrm{}$ and $F_{15}\mathrm{}\left(1680\right)\mathrm{}$ were calculated, using resonance shapes from $\pi -N$ scattering. A quantitative description of the data at $E_{\alpha }=4.2\mathrm{}\mathrm{GeV}$ is obtained using fluid-dynamical transition densities and strengths exhausting large fractions of scalar energy weighted sum rules. The rather pure scalar (non-spin-isospin-flip) character of these excitations and the observed cross sections are in severe conflict with the constituent quark model. Finally, a prediction is made for $p-\alpha$ scattering at an incident energy of $E_p=2.2\mathrm{}\mathrm{GeV},$ which yields strongly increased cross sections for $N^{*}$ excitations.

The fragmentation of a quasiprojectile is studied with the INDRA multidetector for different colliding systems and incident energies in the Fermi energy range. Different experimental observations show that a large part of the fragmentation is not compatible with the statistical fragmentation of a fully equilibrated nucleus. The study of internal correlations is a powerful tool, especially to evidence entrance channel effects. These effects have to be included in the theoretical descriptions of nuclear multifragmentation.

We report a new measurement of the ${\pi }^{-}\overrightarrow{p}3{\pi }^{0}n$ total cross section from threshold to $p_{\pi }=0.75\mathrm{}\mathrm{GeV}/c.\mathrm{}$ The cross section near the $N\left(1535\right)\mathrm{}{\frac{1}{2}}^{-}$ resonance is only a few $\mu \mathrm{b}$ after subtracting the large $\overrightarrow{\eta }3{\pi }^0$ background associated with ${\pi }^{-}\overrightarrow{p}\eta n.\mathrm{}$ A simple analysis of our data results in the estimated branching fraction $\mathcal{B}[S_{11}\to \pi N(1440\left)\mathrm{}{\frac{1}{2}}^{+}\right]=(8\mathrm{}\pm 2)\%.$ This is the first such estimate obtained with a three-pion production reaction.

The knockout of protons from ${}^8\mathrm{B}$ and ${}^9\mathrm{C}$ on a carbon target has been studied at average energies of 76 and 78 MeV/nucleon, respectively, with beams from the A1900 fragment separator incident on a stack of silicon detectors. The following cross sections were obtained: ${\sigma }_{-1\mathrm{p}}{(}^8{\overrightarrow{\mathrm{B}}}^7\mathrm{Be})=130\mathrm{}(11)\mathrm{}\mathrm{mb},$ ${\sigma }_{-1\mathrm{p}}{(}^9{\overrightarrow{\mathrm{C}}}^8\mathrm{B})=54\mathrm{}(4)\mathrm{}\mathrm{mb},$ and ${\sigma }_{-2\mathrm{p}}{(}^9{\overrightarrow{\mathrm{C}}}^7\mathrm{Be})=98\mathrm{}(7)\mathrm{}\mathrm{mb}.$ The results are discussed within the framework of an eikonal approach and compared with measurements performed at higher energies. From this analysis, a consistent picture emerges that gives evidence for the validity of the eikonal approach at energies below 100 MeV/nucleon. Knockout reactions at intermediate energy can thus be used to deduce absolute shell occupancies. We find the spectroscopic factors to be reduced by $R_s$ of 0.86(7) and 0.82(6) for ${}^8\mathrm{B}$ and ${}^9\mathrm{C},$ respectively, relative to shell-model predictions. The ${}^9\mathrm{C}$ result provides an accurate measurement of the asymptotic normalization coefficient of $1.27\left(10\right)\mathrm{}{\mathrm{fm}}^{-1}.$ A new technique is reported for determining separately the contributions from stripping and diffractive breakup.