Heavy baryon/meson ratios ${\Lambda }_c/D^0$ and ${\Lambda }_b/{\overline{B}}^0$ in relativistic heavy ion collisions are studied in the quark coalescence model. For heavy baryons, we include production from coalescence of heavy quarks with free light quarks as well as with bounded light diquarks that might exist in the strongly coupled quark-gluon plasma produced in these collisions. Including the contribution from decays of heavy hadron resonances and also that due to fragmentation of heavy quarks that are left in the system after coalescence, the resulting ${\Lambda }_c/D^0$ and ${\Lambda }_b/{\overline{B}}^0$ ratios in midrapidity ($\left|y\right|⩽0.5$) from central $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{s_{\mathit{NN}}}=200$ GeV are about a factor of five and ten, respectively, larger than those given by the thermal model, and about a factor of ten and twelve, respectively, larger than corresponding ratios in the PYTHIA model for $\mathit{pp}$ collisions. These ratios are reduced by a factor of about 1.6 if there are no diquarks in the quark-gluon plasma. The transverse momentum dependence of the heavy baryon/meson ratios is found to be sensitive to the heavy quark mass, with the ${\Lambda }_b/{\overline{B}}^0$ ratio being much flatter than the ${\Lambda }_c/D^0$ ratio. The latter peaks at the transverse momentum $p_T\simeq 0.8$ GeV but the peak shifts to $p_T\simeq 2$ GeV in the absence of diquarks.

Using the recently published model [Gossiaux and Aichelin, Phys. Rev. C 78, 014904 (2008)] for the collisional energy loss of heavy quarks in a quark gluon plasma (QGP), based on perturbative QCD (pQCD) with a running coupling constant, we study the interaction between heavy quarks and plasma particles in detail. We discuss correlations between the simultaneously produced $c$ and $\overline{c}$ quarks, study how central collisions can be experimentally selected, predict observable correlations, and extend our model to the energy domain of the Large Hadron Collider (LHC). We finally compare the predictions of our model with that of other approaches such as anti-de Sitter/conformal field theory (AdS/CFT).

By means of two different parametrizations of quark energy loss and the nuclear parton distributions determined only with lepton-nuclear deep inelastic scattering experimental data, a leading order phenomenological analysis is performed on the nuclear Drell-Yan differential cross section ratios for E772 experimental data. Uncertainty due to the quark energy loss effect is quantified in determining the nuclear sea quark distribution by using nuclear Drell-Yan data. It is found that the quark energy loss effect on nuclear Drell-Yan cross section ratios becomes greater with the increase of quark momentum fraction in the target nuclei. The uncertainty from the quark energy loss becomes bigger as the nucleus A becomes heavier. The Drell-Yan data on proton incident middle and heavy nuclei versus deuterium would result in an overestimate for nuclear modification in the sea quark distribution with neglecting the quark energy loss.

The neutron-rich $N=66$ isotonic and $A=106$ isobaric chains, covering regions with varying types of collectivity, are interpreted in the framework of the interacting boson model. Level energies and electric quadrupole transition probabilities are compared with available experimental information. The calculations for the known nuclei in the two chains are extrapolated toward the neutron-rich nucleus ${}^{106}\mathrm{Zr}$.

The continuum shell model represents a merger of the traditional shell model, the tool for understanding nuclear structure, with the physics of reactions. In this work a new time-dependent approach to the continuum shell model is presented, where construction and application of the time-dependent evolution operator culminate in an effective and successful strategy for tackling the nonstationary many-body dynamics. Details behind the technique and methods to overcome general problems associated with quantum many-body physics on the verge of stability are discussed. Topics presented include the construction of the time-dependent Green's function, the full propagator from the exact solution of Dyson's equation, a treatment of decays and virtual self-energy terms, the explicit time dependence and survival probability of states, the strength function and collective features of unstable systems, the center-of-mass problem, computation of the cross section and its Blatt-Biedenharn angular decomposition, Coulomb amplitudes, and interference. An extensive comparison with the $R$-matrix approach is offered. Realistic examples are used to demonstrate the techniques.

An analytical expression for the dynamic polarization potential is derived for the elastic scattering of light halo nuclei in the Coulomb field of heavy targets. The derivation is based on the adiabatic motion of the projectile below and close to the Coulomb barrier together with a uniform approximation for the Coulomb functions. Detailed computations have been carried out for the elastic scattering of $d+{}^{208}\mathrm{Pb}$ and ${}^6\mathrm{He}+{}^{208}\mathrm{Pb}$ at collision energies of 8 and 17.8 MeV and are compared with measurements as far as available. The obtained expression for the dynamic polarization potential is simple and can be applied for any arbitrary system with a dineutron configuration.

We show that by requiring positivity of the longitudinal pressure it is possible to constrain the initial conditions one can use in second-order viscous hydrodynamical simulations of ultrarelativistic heavy-ion collisions. We demonstrate this explicitly for $(0+1)$-dimensional viscous hydrodynamics and discuss how the constraint extends to higher dimensions. Additionally, we present an analytic approximation to the solution of $(0+1)$-dimensional second-order viscous hydrodynamical evolution equations appropriate to describe the evolution of matter in an ultrarelativistic heavy-ion collision.

The renormalization of the chiral $\mathit{np}$ interaction with Δ excitations in intermediate states is considered at next-to-leading order and next-to-next-to-leading order for central waves. The inclusion of the Δ excitation as an explicit degree of freedom improves the convergence properties of the effective field theory results for $\mathit{np}$ scattering with respect to Δ-less theory and allows the existence of a deuteron bound state in the infinite cutoff limit. The ${}^1{S}_0$ singlet and ${}^3{S}_1$ triplet phase shifts reproduce data for $p~m_{\pi }$. The role of spectral function regularization is also discussed.

A chiral quark-model approach is extended to the study of the $\overline{K}N$ scattering at low energies. The process $K^{-}p\to {\Sigma }^0{\pi }^0$ at $P_K\lesssim 800$ MeV/$c$ (i.e., the center-of-mass energy $W\lesssim 1.7$ GeV) is investigated. This approach successfully describes the differential cross sections and total cross section with the roles of the low-lying Λ resonances in $n=1$ shells clarified. The $\Lambda (1405)S_{01}$ dominates the reactions over the energy region considered here. Around $P_K\simeq 400$ MeV/$c$, the $\Lambda (1520)D_{03}$ is responsible for a strong resonant peak in the cross section. The $\Lambda (1670)S_{01}$ has obvious contributions around $P_K=750$ MeV/$c$, while the contribution of $\Lambda (1690)D_{03}$ is less important in this energy region. The nonresonant background contributions, i.e., $u$ channel and $t$ channel, also play important roles in the explanation of the angular distributions due to amplitude interferences. The $u$ channel turns out to have significant destructive interferences with the $\Lambda (1405)S_{01}$ at the forward angles. In contrast, the $t$-channel $K^{*}$ exchange has a constructive interference at the forward angles, whereas it suppresses the cross sections slightly at the backward angles. In the $t$ channel, the $K^{*}$ exchange is more dominant than the κ exchange. Our analysis suggests that configuration mixing exists within the $\Lambda (1405)S_{01}$ and $\Lambda (1670)S_{01}$ and results in admixtures of the $[\mathbf{70},{}^2\mathbf{1},1/2]$ and $[\mathbf{70},{}^2\mathbf{8},1/2]$ configurations. The $\Lambda (1405)S_{01}$ is dominated by $[\mathbf{70},{}^2\mathbf{1},1/2]$, and $\Lambda (1670)S_{01}$ by $[\mathbf{70},{}^2\mathbf{8},1/2]$. The mixing angle is also determined. The $\Lambda (1520)D_{03}$ and $\Lambda (1690)D_{03}$ are assigned as $[\mathbf{70},{}^2\mathbf{1},3/2]$ and $[\mathbf{70},{}^2\mathbf{8},3/2]$, respectively.

In the present work we include the isovector-scalar δ meson in the quark-meson coupling (QMC) model and study the properties of asymmetric nuclear within QMC without and with the δ meson. Recent constraints set by isospin diffusion on the slope parameter of the nuclear symmetry energy at saturation density are used to adjust the model parameters. The thermodynamical spinodal surfaces are obtained and the instability region at subsaturation densities within QMC and QMCδ models are compared with mean-field relativistic models. The distillation effect in the QMC model is discussed.

The mixing ratios of $M1$ and $E2$ radiation for transitions in ${}^{11}\mathrm{B}$ have been determined by measuring the azimuthal asymmetry of the radiation emitted from levels populated by resonant absorption of polarized photons. The photon-scattering experiments were carried out at the Free-Electron Laser Laboratory at Duke University using nearly monoenergetic and linearly polarized photon beams. The mixing ratios were deduced from a comparison of the measured azimuthal asymmetries with calculations for the angular distributions of mixed transitions.

In the current study, a simulation technique has been employed to calculate the total potential between two deformed nuclei. It has been shown that this simulation technique is an efficient one for calculating the total potential for all possible orientations between the symmetry axes of the interacting nuclei using the realistic nuclear matter density and the M3Y nucleon-nucleon effective forces. The analysis of the results obtained for the ${}^{48}\mathrm{Ca}+{}^{238}\mathrm{U}$, ${}^{46}\mathrm{Ti}+{}^{46}\mathrm{Ti}$, and ${}^{27}\mathrm{Al}+{}^{70}\mathrm{Ge}$ reactions reveal that considering the density dependent effects in the M3Y forces causes the nuclear potential to drop by an amount of 0.4 MeV.

Double beta decay of ${}^{150}\mathrm{Nd}$ and ${}^{148}\mathrm{Nd}$ to the excited states of daughter nuclei have been studied using a $400\hspace{0.5em}{\mathrm{cm}}^3$ low-background HPGe detector and an external source consisting of 3046 g of natural ${\mathrm{Nd}}_2{\mathrm{O}}_3$ powder. The half-life for the two-neutrino double beta decay of ${}^{150}\mathrm{Nd}$ to the excited $0_1^{+}$ state in ${}^{150}\mathrm{Sm}$ is measured to be $T_{1/2}=[1.33{}_{-0.23}^{+0.36}(\mathrm{stat}){}_{-0.13}^{+0.27}(\mathrm{syst})]\times {10}^{20}$ yr. For other $(0\nu +2\nu )$ transitions to the $2_1^{+}$, $2_2^{+}$, $2_3^{+}$, and $0_2^{+}$ levels in ${}^{150}\mathrm{Sm}$, limits are obtained at the level of $~(2\text{−}8)\times {10}^{20}$ yr. In the case of ${}^{148}\mathrm{Nd}$ only limits for the $(0\nu +2\nu )$ transitions to the $2_1^{+}$, $0_1^{+}$, and $2_2^{+}$ excited states in ${}^{148}\mathrm{Sm}$ were obtained and are at the level of $~(4\text{−}8)\times {10}^{20}$ yr.

By measuring the ${}^{31}\mathrm{P}({}^3\mathrm{He},t){}^{31}\mathrm{S}$, ${}^{31}\mathrm{P}({}^3\mathrm{He},t){}^{31}\mathrm{S}{}^{*}(p){}^{30}\mathrm{P}$, and ${}^{32}\mathrm{S}(d,t){}^{31}\mathrm{S}$ reactions, the level scheme of ${}^{31}\mathrm{S}$ has been refined and extended up to $E_x=9.5$ MeV. A total of 17 new levels, and 5 tentative new levels, have been measured. In addition, 5 tentatively known levels have been confirmed. The uncertainties in the excitation energies of many known ${}^{31}\mathrm{S}$ levels have been reduced substantially. Spin constraints have been made for 8 proton-unbound levels by measuring 18 triton-proton angular correlations from the ${}^{31}\mathrm{P}({}^3\mathrm{He},t){}^{31}\mathrm{S}{}^{*}(p){}^{30}\mathrm{P}$ reaction. Finite proton-decay branching ratios (including discrimination between decays to the ground state and first two excited states of ${}^{30}\mathrm{P}$) have been measured for 38 levels, and upper limits have been set for 3 additional levels. The lowest isospin $T=3/2$ level has been observed, and candidates for the second and third $T=3/2$ levels have been identified. The new experimental information on ${}^{30}\mathrm{P}+p$ resonance parameters has been used together with data from previous measurements to calculate the thermonuclear, resonant ${}^{30}\mathrm{P}(p,\gamma ){}^{31}\mathrm{S}$ reaction rate over three orders of magnitude in temperature: $0.01<T<10$ GK. Good agreement is found with estimates based on Hauser-Feshbach statistical models over the range $0.08<T<10$ GK, but differences are found with rates previously estimated using the experimental information at hand.

The $s$-process branching at mass number $A=176$ depends on the coupling between the high-$K$ ground state and a low-lying low-$K$ isomer in ${}^{176}\mathrm{Lu}$. This coupling is based on electromagnetic transitions via intermediate states at higher energies. The properties of the lowest experimentally confirmed intermediate state at 839 keV are reviewed, and the transition rate between low-$K$ and high-$K$ states under stellar conditions is calculated on the basis of new experimental data for the 839-keV state. Properties of further candidates for intermediate states are briefly analyzed. It is found that the coupling between the high-$K$ ground state and the low-$K$ isomer in ${}^{176}\mathrm{Lu}$ is at least one order of magnitude stronger than previously assumed, leading to crucial consequences for the interpretation of the ${}^{176}\mathrm{Lu}/{}^{176}\mathrm{Hf}$ pair as an $s$-process thermometer.

Based on the properties of the critical and the actual effective masses of sigma and omega mesons, criteria to estimate the values of the isoscalar nonlinear terms of the standard relativistic mean field model that reproduce stable equations of state in respect to particle hole excitation at high densities are derived. The relation between nuclear matter stability and the symmetric nuclear matter properties are shown. The criteria are used to analyze in a more systematic way the high-density longitudinal and transverse instabilities of some parameter sets of relativistic mean field models. The critical role of the vector and vector-scalar nonlinear terms is also discussed quantitatively.

We present a fully relativistic formalism for describing neutrino-induced Δ-mediated single-pion production in nuclei. We assess the ambiguities stemming from the Δ interactions and quantify the uncertainties in the axial form-factor parameters by comparing with the available bubble-chamber neutrino-scattering data. To include nuclear effects, we turn to a relativistic plane-wave impulse approximation (RPWIA) using realistic bound-state wave functions derived in the Hartree approximation to the $\sigma \text{−}\omega$ Walecka model. For neutrino energies larger than 1 GeV, we show that a relativistic Fermi-gas model with appropriate binding-energy correction produces results that are comparable to the RPWIA that naturally includes Fermi motion, nuclear-binding effects, and the Pauli exclusion principle. Including Δ medium modifications roughly halves the RPWIA cross section. Calculations for primary (prior to undergoing final-state interactions) pion production are presented for both electron- and neutrino-induced processes, and a comparison with electron-scattering data and other theoretical approaches is included. We infer that the total Δ-production strength is underestimated by about 20 to $25\%$, a fraction that is due to the pionless decay modes of the Δ in a medium. The model presented in this work can be naturally extended to include the effect of final-state interactions in a relativistic and quantum-mechanical way.

A simple kinematic model based on superposition of $p+p$ collisions, relativistic geometry, and final-state hadronic rescattering is used to calculate various hadronic observables in $\sqrt{s_{\mathit{NN}}}=200$ GeV $\mathrm{Au}+\mathrm{Au}$ collisions and $\sqrt{s_{\mathit{NN}}}=5.5$ TeV $\mathrm{Pb}+\mathrm{Pb}$ collisions. The model calculations are compared with experimental results from several $\sqrt{s_{\mathit{NN}}}=200$ GeV $\mathrm{Au}+\mathrm{Au}$ collision studies. If a short hadronization time is assumed in the model, this model describes the trends of the observables from these experiments surprisingly well considering the model's simplicity. This also gives more credibility to the model predictions presented for $\sqrt{s_{\mathit{NN}}}=5.5$ TeV $\mathrm{Pb}+\mathrm{Pb}$ collisions.

A survey of heavy-ion fusion cross sections at extreme sub-barrier energies has been carried out for lighter systems with positive $Q$ values. A general parametrization is proposed, which describes excitation functions for a wide range of light systems at low energies. This parametrization is then applied to a calculation of excitation functions and $S$ factors for the system ${}^{16}\mathrm{O}+{}^{16}\mathrm{O}$, which has recently been investigated with various other theoretical approaches. It is suggested that this parametrization is useful for estimating sub-barrier fusion cross sections with exotic neutron-rich partners which cannot be studied in the laboratory.

We extend our previous description of the superscaling phenomenon in inclusive electron scattering within the coherent density fluctuation model (CDFM). This model is a natural extension to finite nuclei of the relativistic Fermi gas (RFG) model within which the scaling variable ${\psi }^{\text{'}}$ was introduced. In this work we propose a new modified CDFM approach to calculate the total, longitudinal, and transverse scaling functions built up from the hadronic tensor and the longitudinal and transverse response functions in the RFG model. We test the superscaling behavior of the new CDFM scaling functions by calculating the cross sections of electron scattering (in quasielastic and Δ regions for nuclei with $12⩽A⩽208$ at different energies and angles) and comparing to available experimental data. The new modified CDFM approach is extended to calculate charge-changing neutrino and antineutrino scattering on ${}^{12}\mathrm{C}$ at 1 GeV incident energy.