The STAR Collaboration reported measurements of di-hadron azimuthal correlations in medium-central Au+Au collisions at 200$A$ GeV, where the data are presented as a function of the trigger particle's azimuthal angle relative to the event plane ${\varphi }_s$. In particular, it is observed that the away-side correlation evolves from a single- to a double-peak structure with increasing ${\varphi }_s$. In this work, we present the calculated correlations as functions of both ${\varphi }_s$ and the particle transverse momentum $p_T$, using the hydrodynamic code NeXSPheRIO. The results are found to be in reasonable agreement with the STAR data. We further argue that the above ${\varphi }_s$ dependence of the correlation structure can be understood in terms of the one-tube model, as due to an interplay between the background elliptic flow caused by the initial state global geometry and the flow produced by fluctuations.

Background: The existence of the electric dipole moment (EDM) of stable nuclei would be a direct evidence of the time reversal invariance violation (TRIV). Therefore, its measurement could be considered as a complement to the search for neutron and atomic EDMs.

Purpose: To clarify theoretical issues related to calculations of EDMs in many-body systems we calculated the EDMs of the simplest nuclei.

Method: For calculations of three-nucleon systems EDMs we used TRIV potentials based on the meson exchange theory, as well as the ones derived by using effective field theories (EFT) with and without explicit pions. Nuclear wave functions were obtained by solving Faddeev equations in configuration space for the complete Hamiltonians comprising both TRIV and realistic strong interactions.

Results: The expressions for EDMs of ${}^3\text{He}$ and ${}^3\text{H}$ are given in terms of meson exchange couplings and low energy constants of EFT potentials.

Conclusions: The obtained results are compared with the previous calculations of ${}^3\text{He}$ EDM and with time reversal invariance violating effects in neutron-deuteron scattering. The model dependence on strong interactions is discussed.

The improved Kelson-Garvey (ImKG) mass relations are proposed from the mass differences of mirror nuclei. The masses of 31 measured proton-rich nuclei with $7\le A\le 41$ and $-5\le (N-Z)\le -3$ can be remarkably well reproduced by using the proposed relations, with a root-mean-square deviation of 0.398 MeV, which is much smaller than the results of Kelson-Garvey (0.502 MeV) and isobar-mirror mass relations (0.647 MeV). This is because many more masses of participating nuclei are involved in the ImKG mass relations for predicting the masses of unknown proton-rich nuclei. The masses for 144 unknown proton-rich nuclei with $6\le A\le 74$ are predicted by using the ImKG mass relations. The one- and two-proton separation energies for these proton-rich nuclei and the diproton emission are investigated simultaneously.

In neutron resonances, which are long believed to be a form of quantum chaos, simple regular family structures are found for many even-even nuclei in the several tens of keV to MeV region. Resonance energies can be written by simple arithmetic expressions with good accuracies, where separation energies $S_n$ and $G$ play essential roles and where $G\approx 34.5\mathrm{MeV}$ is almost equal to the Fermi energy. Family structures are described for the observed resonances in ${}^{40}\mathrm{Ca}$, ${}^{54}\mathrm{Cr}$, ${}^{64}\mathrm{Ni}$, ${}^{90}\mathrm{Zr},$ and ${}^{208}\mathrm{Pb}$. Statistical probability tests are performed for the appearance of these family structures. A classical dynamic model of the compound nucleus is proposed where the recurrence of multiple oscillators produces “breathing” and seems to successfully reproduce observed resonance families.

The elliptic flow ($v_2$) of $\varphi$ mesons is shown to be a sensitive probe of the partonic collectivity using a multiphase transport (AMPT) model. Within the ambit of the AMPT model with partonic interactions (string melting version), the $\varphi$-meson $v_2$ at midrapidity is found to have negligible contribution from hadronic interactions for Au+Au collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV. Changing the hadron cascade time in the model calculations does not change the $\varphi$-meson $v_2$, while it reduces the $v_2$ of protons at low transverse momentum ($p_T$). These observations indicate that a substantial reduction in $\varphi$-meson $v_2$ as a function of colliding beam energy would suggest the dominance of hadronic interactions over partonic interactions.

The radioactive isotope ${}^{107}$In was studied using sub-barrier Coulomb excitation at the REX-ISOLDE facility at CERN. Two $\gamma$ rays were observed during the experiment, corresponding to the low-lying $11/2^{+}$ and $3/2^{-}$ states. The reduced transition probability of the $11/2^{+}$ state was determined with the semiclassical Coulomb excitation code gosia2. The result is discussed in comparison to large-scale shell-model calculations, previous unified-model calculations, and earlier Coulomb excitation measurements in the odd-mass In isotopes.

We study the recombination of two neutrons and deuteron into neutron and ${}^3$H using realistic nucleon-nucleon potential models. Exact Alt, Grassberger, and Sandhas equations for the four-nucleon transition operators are solved in the momentum-space framework using the complex-energy method with special integration weights. We find that at astrophysical or laboratory neutron densities the production of ${}^3$H via the neutron-neutron-deuteron recombination is much slower as compared to the radiative neutron-deuteron capture. We also calculate neutron-${}^3$H elastic and total cross sections.

High-spin states in ${}^{184}$Au have been investigated by means of in-beam $\gamma$-ray spectroscopy techniques using the multidetector array of GASP. Excited states of ${}^{184}$Au were populated via the ${}^{159}$Tb(${}^{29}$Si, 4$n$$\gamma$) reaction at a beam energy of 140 MeV. The previously known bands based on the $\pi h_{9/2}\otimes \nu 7/2^{-}\left[514\right]$, $\pi h_{9/2}\otimes \nu 1/2^{-}\left[521\right]$, $\pi h_{9/2}\otimes \nu i_{13/2}$, and $\pi i_{13/2}\otimes \nu i_{13/2}$ configurations have been extended. Three new rotational bands have been identified and assigned as the prolate $\pi 1/2^{+}\left[660\right]\otimes \nu 7/2^{-}\left[514\right]$ and $\pi 11/2^{-}\left[505\right]\otimes \nu 7/2^{-}\left[514\right]$ and oblate $\pi h_{11/2}^{-1}\otimes \nu i_{13/2}^{-1}$ configurations, respectively. Experimental aligned angular momenta, band-crossing frequencies, and electromagnetic properties have been analyzed in the framework of the cranked shell model. Low-spin signature inversion has been observed in the prolate $\pi h_{9/2}\otimes \nu i_{13/2}$ and $\pi i_{13/2}\otimes \nu i_{13/2}$ and oblate $\pi h_{11/2}^{-1}\otimes \nu i_{13/2}^{-1}$ bands of ${}^{184}$Au.

Using a new local cluster potential, cluster structures around double shell closures have been investigated. The calculations of spectra including electromagnetic transitions are in reasonable agreement with experimental data. Besides the nuclei, ${}^{20}$Ne, ${}^{44}$Ti, ${}^{60}$Zn, and ${}^{212}$Po, which have been intensively analyzed by cluster models, we have also studied two other good candidates, ${}^{52}$Ti and ${}^{136}$Te, for $\alpha$-cluster structure in neutron-rich regions. In ${}^{136}$Te, the unexpectedly small $B(E2;0^{+}\to 2^{+})$ would be due to the cluster characteristic. The new cluster potential without any readjustment of the parameter values has been also applied to the investigations of possible ${}^6$He-cluster structure in nuclei, ${}^{22}$Ne, ${}^{46}$Ti, ${}^{54}$Ti, ${}^{62}$Zn, and ${}^{138}$Te, which have the same doubly magic cores as the $\alpha$-cluster nuclei above. Similarly good results can be obtained, compared with experimental data. It is an advantage that the new cluster potential suits the different types of cluster structures with a set of fixed parameters which do not need any readjustment for different cluster-core structures.

The single-neutron properties of $N$ $=$ 51 nuclei have been studied with the ($d$,$p$) and ($\alpha$,${}^3$He) reactions, at beam energies of 15 and 50 MeV respectively, on ${}^{88}$Sr, ${}^{90}$Zr, and ${}^{92}$Mo targets. The light reaction products were momentum analyzed using a conventional magnetic spectrometer. Additionally, the ${}^2{\mathrm{H}(}^{86}\mathrm{Kr},p$) reaction was measured at a beam energy of 10 MeV/u, where outgoing light ions were analyzed using a helical-orbit spectrometer. Absolute cross sections and angular distributions corresponding to the population of different final states in the heavy product were obtained for each reaction. Spectroscopic factors were extracted and centroids of the single-particle strength were deduced. The observations appear consistent with calculations based on an evolution of single-particle structure driven by the nucleon-nucleon forces acting between valence protons and neutrons.

The effect of pairing correlation on transfer reaction below the Coulomb barrier is investigated qualitatively and quantitatively using a simplified version of the time-dependent Hartree-$\mathrm{Fock}+\mathrm{BCS}$ approach. The effect of particle-number symmetry breaking on the description of reaction and dedicated methods to extract one- and two-nucleon transfer probabilities ($P_{1n}$ and $P_{2n}$) in a particle-number symmetry breaking approach are discussed. The influence of pairing is systematically investigated in the ${}^{40}\mathrm{Ca}+{}^{40,42,44,46,48,50}\mathrm{Ca}$ reactions. A strong enhancement of the two-particle transfer probabilities owing to initial pairing correlations is observed. This enhancement induces an increase of the ratio of probabilities $P_{2n}/{\left(P_{1n}\right)}^2$ compared to the case with no pairing. It is shown that this ratio increases strongly as the center-of-mass energy decreases with a value that could be larger than ten in the deep sub-barrier regime. An analysis of the pair transfer sensitivity to the type of pairing interaction, namely surface, mixed, or volume, used in the theory is made. It is found that the pair transfer is globally insensitive to the type of force and depends mainly on the pairing interaction strength.

The new version (incl4.6) of the Liège intranuclear cascade (INC) model for the description of spallation reactions is presented in detail. Compared to the standard version (incl4.2), it incorporates several new features, the most important of which are: (i) the inclusion of cluster production through a dynamical phase space coalescence model, (ii) the Coulomb deflection for entering and outgoing charged particles, (iii) the improvement of the treatment of Pauli blocking and of soft collisions, (iv) the introduction of experimental threshold values for the emission of particles, (v) the improvement of pion dynamics, (vi) a detailed procedure for the treatment of light-cluster-induced reactions taking care of the effects of binding energy of the nucleons inside the incident cluster and of the possible fusion reaction at low energy. Performances of the new model concerning nucleon-induced reactions are illustrated by a comparison with experimental data covering total reaction cross sections, neutron, proton, pion, and composite double-differential cross-sections, neutron multiplicities, residue mass and charge distributions, and residue recoil velocity distributions. Whenever necessary, the incl4.6 model is coupled to the ABLA07 de-excitation model and the respective merits of the two models are then tentatively disentangled. Good agreement is generally obtained in the 200 MeV to 2 GeV range. Below 200 MeV and down to a few tens of MeV, the total reaction cross section is well reproduced and differential cross sections are reasonably well described. The model is also tested for light-ion induced reactions at low energy, below 100 MeV incident energy per nucleon. Beyond presenting the update of the incl4.2 model, attention has been paid to applications of the new model to three topics for which some particular aspects are discussed for the first time. The first topic is the production of clusters heavier than alpha particle. It is shown that the energy spectra of these produced clusters are consistent with coalescence. The second topic regards the longitudinal residue recoil velocity and its fluctuations. Excellent results are obtained for these quantities. It addition, it is shown that the distributions of these quantities display typical random-walk characteristics, at least for not-too-large mass losses. They are interpreted as a direct consequence of the independence of successive binary collisions occurring during the cascade process. The last topic concerns the total reaction cross section and the residue-production cross sections for low-energy incident light ions. It is shown that our new model can give a rather satisfactory account of these cross sections, offering so an alternative to fusion models and the advantage of a single model for the progressive change from fusion to pre-equilibrium mechanisms.

Gamow-Teller (GT) strength in ${}^{40}$Ar is studied by shell-model calculations with monopole-based universal interaction, which has tensor components of $\pi +\rho$-meson exchanges. Calculated GT strength is found to be consistent with the experimental data obtained by recent ($p,n$) reactions. Neutrino capture cross sections on ${}^{40}$Ar for solar neutrinos from ${}^8$B are found to be enhanced compared with previous calculations. The reaction cross sections for multipoles other than $0^{+}$ and $1^{+}$ are obtained by random-phase approximation (RPA). Their contributions become important for neutrino energies larger than 50 MeV.

The 278-keV $M2$ $\gamma$ decay from the $\nu h_{11/2}$ isomeric state in ${}^{113}$Xe has been observed for the first time using the recoil-isomer tagging technique. The half-life of the isomer has been measured to be 6.9(3) $\mu$s. The derived $B\left(M2\right)$ value is in agreement with the trend of systematic measurements of $M2$ transition strengths in neutron-deficient tellurium and tin isotopes. The lifetime of the first excited state in the $\nu h_{11/2}$ band has been measured using the recoil distance Doppler-shift method. The extracted $B\left(E2\right)$ value has been compared to theoretical CD-Bonn calculations and recent lifetime measurements in ${}^{109}$Te. This comparison of $B\left(E2\right)$ values has been used to shed light on the possible influence of collective degrees of freedom on $M2$ transition strengths in the most neutron-deficient xenon nuclei. The $\nu h_{11/2}$ band is deduced to have a degree of deformation comparable with the ground-state bands of the even-mass xenon isotopes. However, the value deduced in this work indicates a loss of collective behavior when compared with the lower-mass ${}^{109}$Te. This result suggests that, while changes in deformation may be partly responsible for the observed trend in $B\left(M2\right)$ values for increasing $Z$, other effects may also be present.

The close similarity between the shell structures in the ${}^{132}$Sn and ${}^{208}$Pb regions is a well known phenomenon. Thus, using the correspondence between the high-$j$ orbits located above the $Z=50$ and $Z=82$ shell gaps, we discuss the evolutions of the fully aligned states with one broken proton pair in the $N=82$ and $N=126$ isotones. A long-lived isomeric state was discovered in ${}^{217}$Pa more than thirty years ago and, despite two other experiments giving new experimental results, the discussions on its main properties (spin, parity, configuration) remained inconclusive. Then, using the comparison with the $I^{\pi }=17/2^{+}$ isomeric state recently measured in ${}^{139}$La, the isomeric state of ${}^{217}$Pa is assigned as the fully aligned state of the ${\left(\pi h_{9/2}\right)}^2{\left(\pi f_{7/2}\right)}^1$ configuration.

Pre-scission neutron multiplicities from fission of the compound nuclei ${}^{210,212,214,216}$Rn have been measured in order to investigate the $N/Z$ dependence of fission hindrance. The Rn isotopes are populated through the fusion of ${}^{16,18}$O $+$ ${}^{194,198}$Pt systems and are formed at four excitation energies in the range of 50–79 MeV. The experimental pre-scission neutron yield is compared with predictions from the statistical model of compound nuclear decay containing the strength of nuclear dissipation as a free parameter. The strength of nuclear dissipation obtained in the present analysis does not show any specific dependence on the $N/Z$ values of the fissioning nuclei at large excitation energies. The dissipation strength at the lowest excitation energy, however, indicates a shell closure effect at $N=126$ for the ${}^{212}$Rn isotope.

We investigate the variation with light quark mass of the mass of the nucleon as well as the masses of the mesons commonly used in a one-boson-exchange model of the nucleon-nucleon force. Care is taken to evaluate the meson mass shifts at the kinematic point relevant to that problem. Using these results, we evaluate the corresponding changes in the energy of the ${}^1{S}_0$ antibound state and the binding energies of the deuteron, triton, and selected finite nuclei by using a one-boson exchange model. The results are discussed in the context of possible corrections to the standard scenario for Big Bang nucleosynthesis in the case where, as suggested by recent observations of quasar absorption spectra, the quark masses may have changed over the age of the Universe.

Excited states in ${}^{74}$Se were populated following the $\epsilon$/${\beta }^{+}$ decay of ${}^{74}$Br, mainly from the $J=K=4$, 13.8-keV $\beta$-decaying isomer. Off-beam $\gamma$-ray spectroscopy was performed with the array of Clover HPGe detectors at WNSL Yale. Many new transitions were observed and rigorous spin assignments were made based on $\gamma$-$\gamma$ angular correlations. The $\beta$-decay strength was found to proceed almost entirely to a few high-lying states near 4500 keV, which are consistent with deformed two-quasineutron high-$K$ configurations. These doorway states then provide an effective tool for populating and identifying the lower prolate structures. Once categorized, the low-lying states of ${}^{74}$Se can be described as a set of near-spherical vibrational levels mixing strongly with a spectrum of prolate states which have an unperturbed bandhead near 1350 keV.