Ground-state energy functions of even-even and odd-$A$ nuclei are derived from simple parameter-dependent Interacting Boson Model (IBM) and Interacting Boson-Fermion Model (IBFM) Hamiltonians. Exact nuclear shape-phase diagrams in the two-parameter ($\eta ,$ $\chi$) plane are explicitly described using the energy functions on the basis of the condition of phase equilibrium.

Systematic calculations on low-lying states are carried out for eighty odd-$A$ nuclei with proton number ranging from 50 to 58 and neutron number from 74 to 90 by using the nucleon pair approximation. We use a separable phenomenological Hamiltonian that includes the monopole pairing, quadrupole pairing plus quadrupole-quadrupole interactions, with strength parameters exactly as those of the neighboring even-even nuclei. Our calculated energy spectra, electrical quadrupole moments, and magnetic $g$ factors agree well with experimental data. Electromagnetic properties for low-lying states of these nuclei are discussed in detail.

Excited states in ${}^{123,125}\mathrm{Sb}$ have been studied following the ${}^{122,124}\mathrm{Sn}$(${}^7\mathrm{Li}$,α2n)${}^{123,125}\mathrm{Sb}$ reactions at beam energies of 35 and 37 MeV, respectively. Conversion coefficients for transitions depopulating isomeric states in ${}^{125}\mathrm{Sb}$ have been measured using an electron spectrometer. This has allowed firm $J^{\pi }$ assignments to be made and enabled the structure of the isomeric states to be compared with those in ${}^{121,127-131}$Sb and in the neighboring even-$A$ tin isotopes. The half-lives of the $J^{\pi }={\frac{23}{2}}^{+}$ isomeric states in ${}^{123}\mathrm{Sb}$ and ${}^{125}\mathrm{Sb}$ have been measured to be 66(4) μs and 272(16) ns, respectively. The half-lives of the $J^{\pi }={\frac{19}{2}}^{+},{\frac{19}{2}}^{-}$, and ${\frac{15}{2}}^{-}$ states in ${}^{125}\mathrm{Sb}$ have been measured as 31(2) ns, 28.0(7) μs, and 4.1(2) μs, respectively. The transition probabilities for the transitions depopulating these states are compared with those in ${}^{121,127-131}$Sb and with the results of shell-model calculations using the Oxbash code and the SN100PN interaction in a restricted model space.

We determine rapidity asymmetry in the production of charged pions, protons, and antiprotons for large transverse momentum ($p_T$) for $d+\mathrm{Au}$ collisions at $\sqrt{s_{\mathit{NN}}}=200$ GeV. The rapidity asymmetry is defined as the ratio of particle yields at backward rapidity (Au beam direction) to those at forward rapidity ($d$ beam direction). The identified hadrons are measured in the rapidity regions $\left|y\right|<0.5$ and $0.5<\left|y\right|<1.0$ for the $p_T$ range $2.5<p_T<10\mathrm{GeV}/\mathrm{c}$. We observe significant rapidity asymmetry for charged pion and proton+antiproton production in both the rapidity regions. The asymmetry is larger for $0.5<\left|y\right|<1.0$ than for $\left|y\right|<0.5$ and is almost independent of particle type. The measurements are compared to various model predictions employing multiple scattering, energy loss, nuclear shadowing, saturation effects, and recombination and also to a phenomenological parton model. We find that asymmetries are sensitive to model parameters and show model preference. The rapidity dependence of ${\pi }^{-}/{\pi }^{+}$ and $\overline{p}/p$ ratios in peripheral $d+\mathrm{Au}$ and forward neutron-tagged events are used to study the contributions of valence quarks and gluons to particle production at high $p_T$.

We calculate nuclear modification factors $R_{d\mathrm{Au}}$, central-to-peripheral ratios, $R_{\mathrm{CP}}$, and pseudorapidity asymmetries $Y_{\mathrm{Asym}}$ in deuteron-gold collisions at $\sqrt{s}=200$ GeV in the framework of leading-order (LO) perturbative quantum chromodynamics. We use the Eskola-Kolhinen-Salgado (EKS), the Frankfurt-Guzey-Strikman (FGS), and the Hirai-Kumano-Nagai (HKN) nuclear parton distribution functions and the Albino-Kramer-Kniehl (AKK) fragmentation functions in our calculations. Results are compared to experimental data from the BRAHMS and STAR collaborations.

In the framework of the Glauber approach applied to the initial stage of ultra-relativistic heavy-ion collisions we analyze the shape parameters of the early-formed system (fireball) and their event-by-event fluctuations. We test a variety of models: the conventional wounded-nucleon model, a model admixing binary collisions to the wounded nucleons, a model with hot spots, and the hot-spot model where the deposition of energy occurs with a superimposed probability distribution. We look in detail at the so-called participant harmonic moments, ${\varepsilon }^{*}$, obtained by an averaging procedure where in each event the system is translated to its center of mass and aligned with the major principal axis of the ellipse of inertia. Quantitative comparisons indicate substantial relative effects for ${\varepsilon }^{*}$ in variants of Glauber models. However, the dependence of the scaled standard deviation $\Delta {\varepsilon }^{*}/{\varepsilon }^{*}$ on the chosen model is weak. For all models the values range from about 0.5 for the central collisions to about 0.3–0.4 for peripheral collisions, for both gold-gold and copper-copper collisions. They are dominated by statistics and change only by 10–15% from model to model. We provide an approximate analytic expansion for the harmonic moments and their fluctuations given in terms of the fixed-axes moments. For central collisions and in the absence of correlations the expansion gives the simple formula $\Delta {\varepsilon }^{*}/{\varepsilon }^{*}\simeq \sqrt{4/\pi -1}=0.52$. Similarly, we obtain expansions for the radial profiles of the higher harmonics. We investigate the relevance of the shape-fluctuation effects for jet quenching and find them important only for very central events. Finally, we make some comments of relevance for hydrodynamics, the elliptic flow, and its fluctuations. We argue how smooth hydrodynamics leads to the known result $v_4~v_2^2$ and, further, to the prediction $\Delta v_4/v_4=2\Delta v_2/v_2$.

Proton resonant states in ${}^{23}\mathrm{Al}$ have been investigated for the first time by the resonant elastic and inelastic scattering of ${}^{22}\mathrm{Mg}$$+p$ with a ${}^{22}\mathrm{Mg}$ beam at 4.38 MeV/nucleon bombarding a thick (CH${}_2$)${}_n$ target. The low-energy ${}^{22}\mathrm{Mg}$ beam was separated by the CNS radioactive ion beam separator (CRIB). The energy spectra of recoiled protons were measured at average scattering angles of ${\theta }_{\mathrm{lab}}\approx 4{}^{°},17{}^{°}$ and $23{}^{°}$. A new state has been observed at $E_x=3.00$ MeV with a spin-parity assignment of ($3/2^{+}$). In addition, resonant inelastic scattering has populated three more states at excitation energies of 3.14, 3.26, and 3.95 MeV, with proton decay to the first excited state in ${}^{22}\mathrm{Mg}$ being observed. The new state at 3.95 MeV has been assigned a spin-parity of $J^{\pi }=(7/2^{+})$. The resonant parameters were determined by an $R$-matrix analysis of the excitation functions with a SAMMY-M6-BETA code. The core-excited structure of ${}^{23}\mathrm{Al}$ is discussed within a shell-model picture. The stellar reaction rate of the ${}^{22}\mathrm{Mg}$($p,\gamma$)${}^{23}\mathrm{Al}$ reaction has been reevaluated, and the revised total reaction rate is about 40% greater than the previous result for temperatures beyond $T_9=0.3$.

A strong $J/\psi$ suppression in central Au+Au collisions has been observed by the PHENIX experiment at the Relativistic Heavy Ion Collider. We develop a hydro$+J/\psi$ model in which hot quark-gluon matter is described by the full (3+1)-dimensional relativistic hydrodynamics and $J/\psi$ is treated as an impurity traversing through the matter. The experimental $J/\psi$ suppression pattern in midrapidity is reproduced well by the sequential melting of ${\chi }_{\mathrm{c}},{\psi }^{\text{'}}$, and $J/\psi$ in dynamically expanding fluid. The melting temperature of directly produced $J/\psi$ is well constrained by the participant-number dependence of the $J/\psi$ suppression and is found to be about $2T_{\mathrm{c}}$ with $T_{\mathrm{c}}$ being the pseudocritical temperature.

At moderately low momentum transfer ($-t$ up to 1 GeV${}^2$) the coupling to the vector meson production channels gives the dominant contribution to real Compton and deeply virtual Compton scattering (DVCS). Starting from a Regge pole approach that successfully describes vector meson production, the singular part of the corresponding box diagrams (where the intermediate vector meson-baryon pair propagates on-shell) is evaluated without any further assumptions (unitarity). Such a treatment explains not only the unexpectedly large DVCS unpolarized cross section that has been recently measured at Jefferson Laboratory (JLab), but also all the beam spin and charge asymmetries that have been measured at JLab and Hermes, without explicit need of Generalized Parton Distributions (GPD). The issue of the relationship between the two approaches is addressed.

Particle-number projection within the Lipkin-Nogami (LN) method is applied to the self-consistent quasiparticle random-phase approximation (SCQRPA), which is tested in an exactly solvable multilevel pairing model. The SCQRPA equations are numerically solved to find the energies of the ground and excited states at various numbers Ω of doubly degenerate equidistant levels. The use of the LN method allows one to avoid the collapse of the BCS (QRPA) to obtain the energies of the ground and excited states as smooth functions of the interaction parameter $G$. The comparison between results given by different approximations such as the SCRPA, QRPA, LNQRPA, SCQRPA, and LNSCQRPA is carried out. Although the use of the LN method significantly improves the agreement with the exact results in the intermediate coupling region, we found that in the strong coupling region the SCQRPA results are closest to the exact ones.

The structure of the neutron-rich isotopes ${}^{59,60}\mathrm{Fe}$ has been studied with the Gammasphere detector array using fusion-evaporation reactions. Level schemes for these nuclei are presented which have been extended to spins of $~20\hslash$. Both isotopes exhibit regular, near-yrast γ-decay sequences which are generated by the intrusion of the $g_{9/2}$ orbital into the $\mathit{fp}$ shell-model space. Lower-spin, natural-parity levels are discussed within the context of shell-model calculations using the GXPF1A interaction in the full $\mathit{fp}$ model space. Experimental features of the high-spin bands are compared with total Routhian surface calculations.

We investigate the energy loss of gluon and quark jets in quark-gluon plasma produced in central Au+Au collisions at RHIC energy ($\sqrt{s_{\mathit{NN}}}=200$ GeV). We use the effective quasiparticle model for investigation of physical characteristics of initial and mixed phases in expanding plasma. In the present work we calculate the quenching weight, i.e., the probability of medium-induced gluon radiation. We show that suppression of ${\pi }^0$ spectra is described correctly by quasiparticle model with increase of running coupling in the region of phase transition (at $T\to T_c$ from above) in agreement with recent lattice calculations and with PHENIX data. We show also that quasiparticle model with decrease of running coupling close to phase transition does not give correct description of this suppression.

We study the shift of the chiral condensate in a constant electromagnetic field in the context of chiral perturbation theory. Using the Schwinger proper-time formalism, we derive a one-loop expression correct to all orders in $m_{\pi }^2/\mathit{eH}$. Our result correctly reproduces a previously derived “low-energy theorem” for $m_{\pi }=0$. We show that it is essential to include corrections due to nonvanishing $m_{\pi }$ for a theorem of low energy to have any approximate regime of validity in the physical universe. We generalize these results to systems containing electric fields and discuss the regime of validity for the results. In particular, we discuss the circumstances in which the method formally breaks down due to pair creation in an electric field.

We present precision measurements of the ${}^3\mathrm{He}+{}^4\mathrm{He}$ $\to$ ${}^7\mathrm{Be}$ reaction in the range $E_{\mathrm{c}.\mathrm{m}.}=0.33$ to 1.23 MeV using a small gas cell and detection of both prompt γ rays and ${}^7\mathrm{Be}$ activity. Our prompt and activity measurements are in good agreement within the experimental uncertainty of several percent. We find $S(0)=0.595\pm 0.018$ keV b from fits of the Kajino theory to our data. We compare our results with published measurements, and we discuss the consequences for Big Bang Nucleosynthesis and for solar neutrino flux calculations.

High precision vector and tensor analyzing power data of the deuteron-proton elastic scattering at 130 MeV deuteron beam energy have been measured in a large range of angles. They are compared with theoretical predictions obtained in various approaches: with realistic potentials for pure $\mathit{NN}$ interactions, with the inclusion of a three-nucleon force, and in the framework of chiral perturbation theory. All the theoretical calculations describe roughly the main features of the measured distributions, but none of them can reproduce all their details. This indicates the need for further development of the three-nucleon force models.

A level scheme has been constructed for the proton-unbound, $T_z=3/2$ nuclide ${}_{53}^{109}{\mathrm{I}}_{56}^{}$ following a recoil-decay-tagging experiment using the ${}^{58}\mathrm{Ni}$(${}^{54}\mathrm{Fe}$, $p2n\gamma$) reaction at a beam energy of 195 MeV. The experiment was performed using the highly efficient JUROGAM γ-ray spectrometer in conjunction with the RITU gas-filled recoil separator and the GREAT focal-plane spectrometer. Cranking calculations are used to interpret band structures built on $\pi g_{7/2}$ and $\pi h_{11/2}$ states in a weakly deformed, triaxial nucleus.

We propose a generalization of the Bjorken in-out Ansatz for fluid trajectories, which, when applied to the 1+1 hydrodynamic equations, generates a one-parameter family of analytic solutions interpolating between the boost-invariant Bjorken picture and the non-boost-invariant one by Landau. This parameter characterizes the proper-time scale when the fluid velocities approach the in-out Ansatz. We discuss the resulting rapidity distribution of entropy for various freeze-out conditions and compare it with the original Bjorken and Landau results.

A relativistic single-particle model is used to calculate the inclusive $(e,e^{\text{'}})$ reaction from $A=12$, 40, 56, 197, and 208 nuclei in the quasielastic region. We have shown that this model provides a very good description of the available experimental cross sections when they are dominated by the quasielastic process. In this paper, we use this model to investigate the dependence of $y$ scaling on electron kinematics, particularly the electron scattering angle, for a range of squared four-momentum transfer of 0.20–0.80 (GeV/$c$)${}^2$. In this kinematic domain, Coulomb distortion of the electron does not significantly affect scaling, but final state interactions of the knocked out nucleon do affect scaling, particularly when the nucleons have lower energies. In general, we find that scaling works for this reaction, but at lower values of the four-momentum transfer, the scaling function does have some dependence on the electron scattering angle. We also consider a modification of $y$ scaling to include small binding energy effects as a function of $Z$ and $A$ and show that there is some improvement in scaling.

We study theoretically the ($K^{-},N$) reactions for the formation of the deeply bound kaonic atoms, which were predicted to be quasistable with narrow widths, using the Green's function method. We systematically consider various cases with different target nuclei and energies and find clear signals in the theoretical spectra for all cases considered in this article. The signals show very interesting structures, such as a RESONANCE DIP instead of a resonance peak. We discuss the origins of the interesting structures and the possibilities of obtaining new information on the existence of kaonic nuclei from the spectra of atomic state formations.

The ($n,\gamma )$ cross section of ${}^{206}\mathrm{Pb}$ has been measured at the CERN n_TOF facility with high resolution in the energy range from 1 eV to 620 keV by using two optimized ${\mathrm{C}}_6{\mathrm{D}}_6$ detectors. In the investigated energy interval about 130 resonances could be observed, from which 61 had enough statistics to be reliably analyzed via the R-matrix analysis code SAMMY. Experimental uncertainties were minimized, in particular with respect to (i) angular distribution effects of the prompt capture γ-rays, and to (ii) the TOF-dependent background due to sample-scattered neutrons. Other background components were addressed by background measurements with an enriched ${}^{208}\mathrm{Pb}$ sample. The effect of the lower energy cutoff in the pulse height spectra of the ${\mathrm{C}}_6{\mathrm{D}}_6$ detectors was carefully corrected via Monte Carlo simulations. Compared to previous ${}^{206}\mathrm{Pb}$ values, the Maxwellian averaged capture cross sections derived from these data are about 20% and 9% lower at thermal energies of 5 keV and 30 keV, respectively. These new results have a direct impact on the $s$-process abundance of ${}^{206}\mathrm{Pb}$, which represents an important test for the interpretation of the cosmic clock based on the decay of ${}^{238}\mathrm{U}$.