Deuteron elastic scattering and stripping processes off a target nucleus consisting of A nucleons are treated within the framework of the few-body integral equations theory. By projecting the ($A+2$)-body operators onto target states, matrix three-body integral equations are derived that allow for the incorporation of the excited states of the target nucleons. This approach is applied to deuteron scattering off ${}^{12}\mathrm{C}$ when the latter is in its ground state before and after the reaction. For the nucleon-${}^{12}\mathrm{C}$ subsystem three sets of (quasi-separable) potentials are employed. The first such potential is based on the one derived by Cattapan et al. [Nucl. Phys. A241, 204 (1975)] for orbital angular momentum states with $L⩽2$, which is valid for low energies. As second set we use the potential of Miyagawa and Koike [Prog. Theor. Phys. 82, 329 (1989)] fitted to semiphenomenological higher-energy phase shifts for states up to $L=6$. The third one finally consists for $3⩽L⩽5$ of the potential set of Miyagawa and Koike, whereas the potential parameters for $L⩽2$ are determined by simultaneously fitting the elastic-channel T matrix obtained as solution of multichannel two-body Lippmann-Schwinger equations, to the experimental low-energy and the semiphenomenological higher-energy phase shifts. For the nucleon-nucleon interaction we take one of the separable ${}^3{S}_1-{}^3{D}_1$ potentials of Phillips [Nucl. Phys. A107, 207 (1968)]. Differential cross sections for the elastic-scattering reaction $d+$${}^{12}\mathrm{C}$ $\to d+$${}^{12}\mathrm{C}$ and the transfer reaction $d+$${}^{12}\mathrm{C}$ $\to p+$${}^{13}\mathrm{C}$(${}^{13}\mathrm{C}$${}^{*}$) are calculated at deuteron bombarding energies of 4.66 and 15 MeV (up to 36-channel calculation), and at 56 MeV (up to 76-channel calculation) together with some selected analyzing powers, and are compared with experimental data. At the highest energy considered, the decomposition of the differential cross section into the near-side and the far-side components shows the appearance of nuclear rainbow scattering.

Multi-breakup processes for the ${}^{124}\mathrm{Sn}$+${}^{64}\mathrm{Ni}$ system at 35 MeV/nucleon have been studied with the forward part of the CHIMERA detector. An extensive comparison between experimental data corresponding to almost complete ternary events and constrained molecular dynamics (CoMD-II) calculations suggests different characteristic times in the selected processes. This is in agreement with previous studies of the same reaction already published concerning the prompt intermediate-mass-fragment emission. Stimulated by CoMD-II calculations, we investigate the existence of more complex dynamical multi-breakup processes occurring on the same time scale. A detailed study of the rotational dynamics leading to slower dynamical fission processes is also presented.

We calculate nuclear shadowing ratios at small Bjorken-$x$ for nuclei in the mass range $3<A<239$ in the framework of a generalized form of the Gribov theory. The diffractive dissociation cross sections needed as inputs are taken from the FNAL (Fermi National Laboratory) and HERA (Hadron-Electron Ring Accelerator) experiments. Our calculations cover a wide range of energies between 12.8 and 231 GeV. The effects of the inclusion of subleading Reggeons on nuclear shadowing are investigated. At lower energies our results are compared to available data from the New Muon Collaboration (NMC) and E665 Collaboration (E665) experiments at $x\simeq {10}^{-4}$. At higher energies subleading Reggeons are found to contribute significantly to nuclear shadowing.

The data analysis for the reaction ${}^1\mathrm{H}$$(e,e^{\text{'}}{\pi }^{+})n$, which was used to determine values for the charged pion form factor $F_{\pi }$ for values of $Q^2=$ 0.6–1.6 GeV${}^2$, has been repeated with careful inspection of all steps and special attention to systematic uncertainties. Also the method used to extract $F_{\pi }$ from the measured longitudinal cross section was critically reconsidered. Final values for the separated longitudinal and transverse cross sections and the extracted values of $F_{\pi }$ are presented.

The properties of Λ hyperons in pure Λ matter are studied with the finite-density quantum chromodynamics (QCD) sum rule approach. The first-order quark and gluon condensates in Λ nuclear matter are deduced from the chiral perturbation theory. The sum-rule predictions are sensitive to the four-quark condensates, $\langle \overline{q}q{\rangle }_{\rho }^2$ and $\langle \overline{q}q\rangle {}_{\rho }\langle \overline{s}s\rangle {}_{\rho }$, and the $\pi N$ sigma term. When $\langle \overline{q}q{\rangle }_{\rho }^2$ is nearly independent of density and $\langle \overline{q}q\rangle {}_{\rho }\langle \overline{s}s\rangle {}_{\rho }$ depends strongly on density, we can obtain weakly attractive $\Lambda \Lambda$ potentials (about several MeV) in the low Λ density region, which agrees with the information from the latest double Λ hypernucleus experiments. The nearly no-density dependence of $\langle \overline{q}q{\rangle }_{\rho }^2$ and strong density dependence of $\langle \overline{q}q\rangle {}_{\rho }\langle \overline{s}s\rangle {}_{\rho }$ can be explained naturally if the properties of $\langle \overline{q}q{\rangle }_{\rho }^2$ and $\langle \overline{q}q\rangle {}_{\rho }\langle \overline{s}s\rangle {}_{\rho }$ are assumed to be similar to those of $\pi \pi$ and $\overline{K}K$ in nuclear medium, respectively.

The nucleon form factors of the energy-momentum tensor are studied in the large-$N_c$ limit in the framework of the chiral quark-soliton model for model parameters that simulate physical situations in which pions are heavy. This allows for a direct comparison to lattice quantum chromodynamics results.

Coulomb effects during the interaction of light deformed projectile nuclei with a heavy collision partner have been predicted to modify the fusion barrier distribution leading to a hindrance in the sub-barrier fusion cross section. In order to verify this experimentally, we have determined the fusion barrier distributions from the measurement of quasielastic excitation functions for ${}^{16}\mathrm{O}$(spherical)+${}^{115}\mathrm{In}$, ${}^{28}\mathrm{Si}$(oblate)+ ${}^{115}\mathrm{In}$, and ${}^{30}\mathrm{Si}$(prolate)+ ${}^{115}\mathrm{In}$ systems. For ${}^{16}\mathrm{O}+{}^{115}\mathrm{In}$ system, the fusion barrier distribution is single peaked, whereas for ${}^{28}\mathrm{Si}+{}^{115}\mathrm{In}$ and ${}^{30}\mathrm{Si}+{}^{115}\mathrm{In}$ systems, one observes broadening and well defined structures in fusion barrier distribution, which could be explained by coupled-channel calculations performed using the CCFULL code after including deformation and Coulomb effects on the projectile in the field of target nucleus.

We discuss the prospects of extracting information on bulk QCD matter distribution and evolution on the basis of hard hadronic back-to-back correlations in ultrarelativistic heavy-ion collisions. Using both hydrodynamic and parametrized evolution models for the space-time evolution of produced matter, which have been tested against data from the BNL Relativistic Heavy-Ion Collider, we study six different setups for the space-time dependence of hard-parton energy losses. Assuming that the energy loss of hard partons traversing the medium is radiative and calculable in the Baier-Dokshitzer-Mueller-Peigné-Schiff formalism, we adjust one parameter, the quenching power scale, to the measured nuclear suppression factor $R_{\mathit{AA}}$ in each of the setups and study the systematic variations of the back-to-back yield as a function of transverse momentum $p_T$. We show which space-time regions are probed by one- and two-particle observables and study in some detail the role of longitudinal and transverse expansion. We also comment on the importance of considering fluctuations around the average energy loss. We conclude that while current data are too limited in momentum coverage, future data for higher trigger energy might provide the lever arm in away-side hadron momentum necessary to perform medium tomography, provided that sufficient precision can be achieved.

Based on the adiabatic picture for heavy-ion reactions, in which the neck formation in the one-body system is taken into account, we propose a two-step model for fusion cross sections at deep sub-barrier energies. This model consists of the capture process in the two-body potential pocket, which is followed by the penetration of the adiabatic one-body potential to reach a compound state after the touching configuration. We describe the former process with the coupled-channels framework, while the latter with the Wentzel-Kramers-Brillouin (WKB) approximation by taking into account the coordinate dependent inertia mass. The effect of the one-body barrier is important at incident energies below the potential energy at the touching configuration. We show that this model well accounts for the steep fall-off phenomenon of fusion cross sections at deep sub-barrier energies for the ${}^{64}\mathrm{Ni}$+${}^{64}\mathrm{Ni}$ and ${}^{58}\mathrm{Ni}$+${}^{58}\mathrm{Ni}$ reactions.

The shape coexistence phenomena in ${}^{189}\mathrm{Tl}$ are investigated by measuring the lifetimes of the high spin states through the recoil distance LIFETIME measurement technique. For this study, the ${}^{165}\mathrm{Ho}$(${}^{28}\mathrm{Si}$, $4n)$${}^{189}\mathrm{Tl}$ reaction at a beam energy of 138 MeV was used. In this measurement, the lifetimes of four levels of the negative parity $\pi h_{9/2}$ band and seven levels of the positive parity $\pi i_{13/2}$ band are found. The extracted transition quadrupole moments for the positive parity $\pi i_{13/2}$ band show interesting changes with increasing level spin. This band starts with a small oblate shape ($Q_t=1.1$ $e$ b) at low spin ($17/2^{+}$) and attains a strongly deformed prolate shape ($Q_t=8.8$ $e$ b) at high spins ($33/2^{+}$). On the other hand, the negative parity $\pi h_{9/2}$ band shows a stable oblate structure against the increasing spin with an average quadrupole moment ($Q_t$) of ∼2.6 $e$ b. To better understand the shape coexistence phenomena in ${}^{189}\mathrm{Tl}$ nucleus, the experimental results are also compared with the results of the total Routhian surfaces calculations, for the positive parity $\pi i_{13/2}$ and the negative parity $\pi h_{9/2}$ bands in this nucleus. The comparison confirms the shape coexistence structure of the ${}^{189}\mathrm{Tl}$ nucleus in the positive parity $\pi i_{13/2}$ configuration.

Light fragments emitted in ${}^{86}\mathrm{Kr}$-${}^{124}\mathrm{Sn}$ collisions at intermediate energy ($E_{\mathrm{beam}}=25$ MeV/nucleon) and larger impact parameters ($b=7\text{−}10$ fm) are studied by a multisource ideal gas model. The momentum component, transverse momentum, and azimuthal angle distributions of light fragments with mass numbers $A=1\text{−}4$ are given. Meanwhile, the correlation between the elliptic flow and transverse momentum, as well as the correlation between the fourth momentum anisotropy and transverse momentum for the mentioned light fragments are given, too. The calculated results are compared with the theoretical results of the Isospin-Dependent Quantum Molecular Dynamics model.

Working within the framework of the Coulomb modified Glauber model, we analyze the elastic angular distribution and reaction cross section for the ${}^{12}\mathrm{C}$-${}^{12}\mathrm{C}$ system at 1.016, 1.449, and 2.4 GeV. The elastic $S$ matrix is evaluated using the effective profile function approach, and a correlation expansion for the Glauber amplitude is obtained. We emphasize the parametrization of the basic (input) $\mathit{NN}$ amplitude, which may be used for a wide range of angles. Retaining the first two terms of the correlation expansion and using the realistic densities for the colliding nuclei, we find that (i) the consideration of higher momentum transfer components, and hence the nondiffractive behavior, of the $\mathit{NN}$ amplitude provides a more satisfactory account of the data than does the conventional (one-term) Gaussian parametrization for the $\mathit{NN}$ amplitude, (ii) the in-medium effects seem to reduce the (free) $\mathit{NN}$ total cross section and influence the other parameters of the $\mathit{NN}$ amplitude as well, (iii) the phase of the $\mathit{NN}$ amplitude does not help in improving the theoretical situation, and (iv) the c.m. correlations play an important role at the energies considered. We also discuss the suitability of the effective profile function approach in the present context.

The high-spin structure of the ${}^{135}\mathrm{Xe}$ isotope was studied via prompt γ-ray spectroscopy in two different experiments: (i) as a fission fragment following the fission of the ${}^{226}\mathrm{Th}$ compound nucleus formed in a fusion-fission reaction and (ii) as an evaporation residue in the ${}_{136}\mathrm{Xe}(n,2n\gamma$)${}^{135}\mathrm{Xe}$ reaction. The level scheme above the previously known $11/2^{-}$ isomer was established up to 3170-keV excitation energy. A strong sequence has been firmly assigned to ${}^{135}\mathrm{Xe}$ and forms the yrast decay path including the $(15/2^{-}$) and $(19/2^{-}$) states. A much weaker sequence of γ rays has been observed and tentatively assigned to ${}^{135}\mathrm{Xe}$ and is a candidate for the off-yrast sequence that includes the $(13/2^{-}$) and $(17/2^{-}$) states, expected in the weak coupling of the $h_{11/2}$ neutron to the even-$A$ core. The experimental results are compared with predictions from shell-model calculations.

The semiclassical approach has proven to be a most valuable tool for the construction of the scattering matrix and accurate evaluation of cross sections in a large variety of heavy-ion collision problems. In its familiar implementation, however, its use is restricted to what is now known as the “regular regime”, as it makes use of classical reaction functions that must be continuous and interpolable. In this paper we identify what version of the semiclassical formalisms may be especially suitable for extension into the chaotic regime that develops at energies close to the Coulomb barrier. We also show the crucial role of the absorptive part of the ion-ion potential to retain the usefulness of the semiclassical methods under conditions of irregularity.

Nuclear model calculations of discrete γ-ray production cross sections produced in ${}^{48}\mathrm{Ti}$($n,n^{\text{'}}{\gamma }_i$)${}^{48}\mathrm{Ti}$ and ${}^{48}\mathrm{Ti}$($n,2n{\gamma }_i$)${}^{47}\mathrm{Ti}$ reactions were made as a function of incident neutron energy from $E_n=1$ MeV to 35 MeV and compared with new experimental results using the large-scale Compton-suppressed germanium array for neutron induced excitations (GEANIE) at LANSCE. The Hauser-Feshbach reaction code GNASH, incorporating the spin distribution for the preequilibrium process calculated with the Feshbach-Kerman-Koonin (FKK) quantum-mechanical preequilibrium theory, was used to calculate partial γ-ray transition cross sections. The comparisons of calculated and experimental data demonstrate that, the FKK model for preequilibrium leads a better overall reproduction of the experimental data above $E_n=10$ MeV, where preequilibrium processes are important. The FKK calculation predicts a strong reduction in the high-spin state population in ${}^{48}\mathrm{Ti}$ by inelastic scattering. Population of low-spin states was also affected, however the change in the low-lying 983.5-keV ($2^{+}$) state production is small because almost all γ-ray decay cascades feed this transition. In addition, the FKK calculation has a significant impact on the partial γ-ray transition cross sections for the ($n,2n$) reaction above $E_n=15$ MeV. The calculated cross sections for high-spin states in ${}^{47}\mathrm{Ti}$ are reduced, and those from the low-spin states are enhanced, in agreement with the experimental cross section data.

We calculate the transverse momentum and invariant mass dependence of elliptic flow of thermal dileptons for Au+Au collisions at the Relativistic Heavy Ion Collider. The system is described using hydrodynamics, with the assumption of formation of a thermalized quark-gluon plasma at some early time, followed by cooling through expansion, hadronization, and decoupling. Dileptons are emitted throughout the expansion history: by annihilation of quarks and antiquarks in the early quark-gluon plasma stage and through a set of hadronic reactions during the late hadronic stage. The resulting differential elliptic flow exhibits a rich structure, with different dilepton mass windows providing access to different stages of the expansion history. Elliptic flow measurements for dileptons, combined with those of hadrons and direct photons, are a powerful tool for mapping the time evolution of heavy-ion collisions.

The effects of initial-state Coulomb interactions in the charge-symmetry-breaking reaction $\mathit{dd}\to \alpha {\pi }^0$ are investigated within a previously published formalism. This is a leading order effect in which the Coulomb interaction between the two initial state protons leads to the breakup of the two deuterons into a continuum state that is well connected to the final $\alpha {\pi }^0$ state by the strong emission of a pion. As a first step, we use a simplified set of $d$ and α wave functions and a plane-wave approximation for the initial $\mathit{dd}$ state. This Coulomb mechanism, by itself, yields cross sections that are much larger than the experimental ones, and which are comparable in size to the contributions from other mechanisms. Inclusion of this mechanism is therefore necessary in a realistic calculation.

We analyze the neutrino induced charged current coherent pion production at the energies of interest for recent experiments like K2K and MiniBooNE. Medium effects in the production mechanism and the distortion of the pion wave function, obtained solving the Klein Gordon equation with a microscopic optical potential, are included in the calculation. We find a strong reduction of the cross section due to these effects and also substantial modifications of the energy distributions of the final lepton and pion.