Background: Recent data on $N=80$ isotones have suggested that the proton $\pi \left(1g_{7/2}\right)$ subshell closure at $Z=58$ has an impact on the properties of low-lying collective states.

Purpose: Knowledge of the $B(E2;2_1^{+}\to 0_1^{+})$ value of ${}^{140}$Nd is needed in order to test this conjecture.

Method: The unstable, neutron-rich nucleus ${}^{140}$Nd was investigated via projectile Coulomb excitation at the REX-ISOLDE facility with the MINIBALL spectrometer.

Results: The $B\left(E2\right)$ value of 33(2) W.u. expands the $N=80$ systematics beyond the $Z=58$ subshell closure.

Conclusions: The measurement demonstrates that the reduced collectivity of ${}^{138}$Ce is a local effect possibly due to the $Z=58$ subshell closure and requests refined theoretical calculations. The latter predict a smoothly increasing trend.

We obtain a detailed description of all available hadron multiplicity yields in central Pb-Pb collisions at the CERN Large Hadron Collider (LHC) measured in the rapidity interval $\left|y\right|<0.5$. We find that the hadronization of the fireball at the LHC occurs at nearly identical intensive physical bulk conditions for all centralities similar to those already seen at the Brookhaven National Laboratory Relativistic Heavy Ion Collider.

A multi-Pomeron exchange potential (MPP) is proposed as a model for the three-body repulsion indicated in neutron-star matter, which works universally among three and four baryons. Its strength is determined by analyzing the nucleus-nucleus scattering with the $G$-matrix folding model. The equation of state in neutron matter is obtained including the MPP contribution. The neutron-star mass is calculated by solving the Tolmann-Oppenheimer-Volkof equation. The maximum mass is obtained to be larger than the observed one, $1.97M_{\mathrm{solar}}$, on the basis of the experimental data.

Background: Giant dipole resonance (GDR) has been used as an important tool for studying nuclear properties in hot rotating nuclei. Exclusive measurements using low-energy $\gamma$-ray multiplicity filters provide more control over angular momentum selection in such measurements.

Purpose: Study the effect of angular momentum and temperature on nuclear deformations and GDR widths at high excitation energies in ${}^{144}$Sm.

Methods: Exclusive measurements of GDR $\gamma$ rays were carried out in the ${}^{28}$Si+${}^{116}$Cd reaction populated at two different excitation energies. Beam energies of 125 and 140 MeV pumped the nuclei to average temperatures $\langle T\rangle$ of 1.1 to 1.5 MeV. The high-energy $\gamma$ rays were measured using the large NaI(Tl) detector in coincidence with the sum-spin multiplicity filter consisting of 32 NaI(Tl) detectors covering nearly 4$\pi$ sr of solid angle.

Results: The average angular momentum $\langle J\rangle$ spanned the range of 25$\hslash$ to 60$\hslash$. The GDR centroid energies, widths, and deformation parameter ($\beta$) were extracted as a function of $\langle J\rangle$ at three different $\langle T\rangle$ bins of 1.1, 1.3, and 1.5 MeV. The thermal shape fluctuation model (TSFM) calculations have been performed incorporating the fluctuations induced due to temperature and deformation in the nucleus using a numerically exact method. The calculations showed evidence of deformation throughout the experimental range. The GDR width data have been interpreted in terms of reduced width as a function of reduced angular momentum.

Conclusions: The nucleus evolves to a deformed shape from spherical shape in ground state in the extracted temperature range as predicted by the theoretical calculations. Kusnezov's parametrization also holds good for the large experimental $J$ range.

Lifetime measurements have been carried out for high spin states in ${}^{123}$Cs and ${}^{124}$Ba using the Doppler shift attenuation method. The transition quadrupole moments $Q_t$ measured in the present work show a loss of collectivity after the alignment of neutron $h_{11/2}$ orbitals. The experimental results are compared with the existing theoretical calculations within the framework of the cranked shell model. The results are consistent with the evolution of triaxial shape due to the alignment of $\nu h_{11/2}$ orbitals. However, larger deformation parameters ${\beta }_2$ have been measured compared with the values predicted by the model calculations in both the nuclei.

In this work we studied $\beta$-decay properties for deformed neutron-rich nuclei in the region $Z=36$–43. We use the deformed $pn$-QRPA (quasiparticle-random-phase approximation) methods with the realistic CD-Bonn forces, and include both the Gamow-Teller and first-forbidden types of decays in the calculation. The obtained $\beta$-decay half-lives and neutron-emission probabilities of deformed isotopes are compared with experiment as well as with previous calculations. The advantages and disadvantages of the method are discussed.

We measured the reaction cross sections of the two-neutron halo nucleus ${}^{11}$Li with solid hydrogen and carbon targets at around 31 and 41 MeV/nucleon. The neutron density distribution of ${}^{11}$Li was deduced for the first time by the Glauber model calculation based on the optical limit approximation. The uncertainty of the matter density of ${}^{11}$Li was improved, compared with earlier measurements. The present root-mean-square radius of the proton distribution agrees with the previous one derived from an optical isotope shift measurement. The present root-mean-square radii reproduce theoretical calculations by the tensor optimized shell model by assuming core excitation. This consistency suggests the possibility that ${}^9$Li in ${}^{11}$Li is excited and the disappearance of the $N=8$ shell gap of ${}^{11}$Li is caused by correlations originating from the nucleon force, such as the tensor and the pairing.

Isomeric ratios have been determined for 23 metastable states identified in $A\approx 200$ nuclei from Pt to Rn near the valley of stability following fragmentation of ${}^{238}$U. This includes high-spin states with angular momenta ranging from (39/2)$\hslash$ to 25$\hslash$. The experimental results are discussed together with those of similar experiments performed in this mass region. Isomeric ratios are compared with theoretical predictions where the angular momentum of the fragment arises purely due to the angular momentum of nucleons removed from the projectile. The theoretical yield of low-spin states is generally overestimated. In these cases the assumption of 100$\%$ feeding of the isomer may require modification. However, the yield of high-spin isomeric states [$I_m$ $\ge$ (39/2)$\hslash$] is significantly underestimated and highlights the requirement for a more complete theoretical framework in relation to the generation of fragment angular momentum. The enhanced population of high-spin states reported here is advantageous to future studies involving isomeric beams at fragmentation facilities such as the Rikagaku Kenkyusho RI Beam Factory (Japan) and next-generation facilities at the Facility for Antiproton and Ion Research (Germany) and Facility for Rare Isotope Beams (USA).

Results of the analysis of the MiniBooNE experiment data for the neutral current elastic neutrino scattering off the ${\text{CH}}_2$ target with the NuWro Monte Carlo generator are presented. The inclusion in the analysis of the two-body current contribution leads to the axial mass value $M_A=1.{10}_{-0.15}^{+0.13}$ GeV, consistent with the older evaluations based on the neutrino-deuteron scattering data. The strange quark contribution to the nucleon spin is estimated with the value $g_A^s=-0.4_{-0.3}^{+0.5}$.

We study the energy momentum deposited by fast moving partons within a medium using linearized viscous hydrodynamics. The particle distribution produced by this energy momentum is computed using the Cooper-Frye formalism. We show that, for the conditions arising in heavy-ion collisions, energy momentum is preferentially deposited along the head shock of the fast moving partons. We also show that the double hump in the away-side of azimuthal correlations can be produced by two (instead of one) away-side partons that deposit their energy momentum along their directions of motion. These partons originate in the in-medium hard scattering in $2\to 3$ processes. We compare the results of the analysis to azimuthal angular correlations from PHENIX and show that the calculation reproduces the data systematics of a decreasing away-side correlation when the momentum of the associated hadron becomes closer to the momentum of the leading hadron. This scenario seems to avoid the shortcomings of the Mach cone as the origin of the double-hump structure in the away-side.

The isoscalar giant monopole resonances (ISGMRs) in ${}^{90,92,94}$Zr and ${}^{92,96,98,100}$Mo have been studied with inelastic scattering of 240-MeV α particles at small angles including 0${}^{\mathrm{o}}$. Strength corresponding to approximately 100% of the ISGMR ($E$0) energy-weighted sum rule was identified in each nucleus. In all cases the strength consisted of two components separated by 7–9 MeV. Except for the mass 92 nuclei, the upper component contained 14–22% of the $E$0 energy-weighted sum rule (EWSR); however 38% and 65% of the $E$0 EWSR were located in the upper components in ${}^{92}$Zr and ${}^{92}$Mo, respectively. The energies of the ISGMRs for ${}^{92}$Zr and ${}^{92}$Mo are 1.22 and 2.80 MeV, respectively, higher than for ${}^{90}$Zr, suggesting a significant nuclear structure contribution to the energy of the ISGMR in these nuclei. This has a large effect on the compression modulus of the nucleus with the values extracted for ${}^{92}$Zr and ${}^{92}$Mo being 27 and 56 MeV, respectively, higher than that for ${}^{90}$Zr.

A high-statistics, high-resolution, complete kinematical measurement has been performed to estimate the quantitative contributions of various direct 3$\alpha$ decay mechanisms in the decay of the famous Hoyle state, the $0_2^{+}$ resonant excited state of ${}^{12}$C at an excitation energy of 7.654 MeV, using inelastic scattering of 60-MeV $\alpha$ particles on ${}^{12}$C. The present observation of nonzero branching ratios of various direct 3$\alpha$ decay modes, which have been extracted using $\sim$20$$000 fully detected (4$\alpha$) Hoyle events, is expected to remove the ambiguities among various previous estimates, extracted from fewer ($\lesssim$5000) events.

Following a previous paper [Liang et al., Phys. Rev. C 87, 014334 (2013)], we discuss spin-orbit effects on pseudospin symmetry (PSS) within the framework of supersymmetric quantum mechanics. By using perturbation theory, we demonstrate that the perturbative nature of PSS maintains when a substantial spin-orbit potential is included. With the explicit PSS-breaking potential, the spin-orbit effects on the pseudo-spin-orbit splittings are investigated in a quantitative way.

A recently proposed method, based on quadrupole and multiplicity fluctuations in heavy ion collisions, is modified in order to take into account distortions due to the Coulomb field. This is particularly interesting for bosons, such as $d$ and $\alpha$ particles, produced in heavy ion collisions. We derive the temperatures and densities seen by the bosons and compare them to results of similar calculations for fermions. The resulting energy densities agree rather well with each other and with the one derived from neutron observables. This suggests that a common phenomenon, such as the sudden opening of many reaction channels and/or a liquid-gas phase transition, is responsible for the agreement.

Intermediate energy data of proton-induced fission on ${}^{241}$Am, ${}^{238}$U, and ${}^{237}$Np targets were analysed and investigated using the computational simulation code crisp. Inelastic interactions of protons on heavy nuclei and both symmetric and asymmetric fission are regarded. The fission probabilities are obtained from the crisp code calculations by means of the Bohr-Wheeler model. The fission cross sections, the fissility and the number of nucleons evaporated by the nuclei, before and after fission, are calculated and compared with experimental data. Some of the model predictions agree completely with the data. We conclude that our two step model of the crisp code provides a good description of intermediate energy proton-induced fission.

The experimental determination of freeze-out temperatures and densities from the yields of light elements emitted in heavy ion collisions is discussed. Results from different experimental approaches are compared with those of model calculations carried out with and without the inclusion of medium effects, which become of relevance for baryon densities above $\approx$$5\times {10}^{-4}$ fm${}^{-3}$. A quantum statistical (QS) model incorporating medium effects is in good agreement with the experimentally derived results at higher densities. A densitometer based on medium modified chemical equilibrium constants is proposed.

Storage-ring mass spectrometry was applied to neutron-rich ${}^{197}$Au projectile fragments. Masses of ${}^{181,183}$Lu, ${}^{185,186}$Hf, ${}^{187,188}$Ta, ${}^{191}$W, and ${}^{192,193}$Re nuclei were measured for the first time. The uncertainty of previously known masses of ${}^{189,190}$W and ${}^{195}$Os nuclei was improved. Observed irregularities on the smooth two-neutron separation energies for Hf and W isotopes are linked to the collectivity phenomena in the corresponding nuclei.

Two pairs of nearly degenerate doublet bands in ${}^{107}$Ag are studied via the relativistic mean-field (RMF) theory and the multiparticle plus rotor model (PRM), which suggests these bands as two distinct sets of chiral doublet bands. For the suggested $\pi g_{9/2}^{-1}\otimes \nu h_{11/2}^2$ and $\pi g_{9/2}^{-1}\otimes \nu h_{11/2}{d}_{5/2}$ configurations, the favorable triaxial deformation $\gamma$ for nuclear chirality can be obtained from the configuration-fixed constrained triaxial RMF calculations. Adopting the PRM, the data available are reproduced very well for the two pairs of doublet bands. Chiral geometry is further conformed by analyzing the angular momentum components. We suggest that two pairs of doublet bands in ${}^{107}$Ag would be another example of multiple chiral doublet bands.

The inelastic scattering of neutrons on structural materials constitutes a major concern for the design of neutrinoless double $\beta$ decay experiments. We explore our neutron inelastic scattering data on ${}^{206}$Pb, ${}^{56}$Fe, ${}^{28}$Si, ${}^{24}$Mg, and ${}^{12}$C, searching for possible contributors to the background in the energy region where neutrinoless double $\beta$ decay signals would be produced.

Thermodynamic and transport properties of nuclear fireball created in the central region of heavy-ion collisions below 400 MeV/nucleon are investigated within the isospin-dependent quantum molecular dynamic (IQMD) model. These properties, including the density, temperature, chemical potential, entropy density ($s$), and shear viscosity ($\eta$), are calculated by a generalized hot Thomas Fermi formulism and a parametrized function, which was developed by Danielewicz. As the collision goes on, a transient minimal $\eta /s=5/4\pi -10/4\pi$ occurs in the largest compression stage. Besides, the relationship of $\eta /s$ to temperature ($T$) in the freeze-out stage displays a local minimum which is about 9–20 times $1/4\pi$ around $T=8$–12 MeV, which can be argued as indicative of a liquid gas phase transition. In addition, the influences of nucleon-nucleon (NN) cross section (${\sigma }_{\mathit{NN}}$) and symmetry energy coefficient ($C_s$) are also discussed, and it is found that the results are sensitive to ${\sigma }_{\mathit{NN}}$ but not to $C_s$.