Recently the measured proton-${}^9\mathrm{C}$ elastic angular distribution at 300 MeV/nucleon had been analyzed within the Brueckner-Hartree-Fock framework. The Argonne v-18 internucleon potential was used to generate the reaction matrices which were then folded over ${}^9\mathrm{C}$ density distributions obtained by using the relativistic mean-field model. The calculations yield a satisfactory agreement with the experimental data.

New positive-parity states, having a bandlike structure, were observed in ${}^{105}\mathrm{Ru}$. The nucleus was produced in an induced fission reaction, and the prompt $\gamma$-rays, emitted from the fragments, were detected by the EUROBALL III multidetector array. The partial scheme of excited ${}^{105}\mathrm{Ru}$ levels is analyzed within the triaxial-rotor-plus-particle approach.

Charge symmetry breaking contributions to the proton's neutral weak form factors must be understood in order for future measurements of parity violating electron-proton scattering to be definitively interpreted as evidence of proton strangeness. We calculate these charge symmetry breaking form factor contributions using chiral perturbation theory with resonance saturation estimates for unknown low-energy constants. The uncertainty of the leading-order resonance prediction is reduced by incorporating nuclear physics constraints. Higher-order contributions are investigated through phenomenological vertex form factors. We predict that charge symmetry breaking form factor contributions are an order of magnitude larger than expected from naïve dimensional analysis but are still an order of magnitude smaller than current experimental bounds on proton strangeness. This is consistent with previous calculations using chiral perturbation theory with resonance saturation.

We investigate the effect of high-order radiative corrections in unpolarized electron proton elastic scattering and compare with the calculations at lowest order, which are usually applied to experimental data. Particular attention is devoted to the $\epsilon$ dependence of radiative corrections, which is directly related to the electric-proton form factor. We consider in particular the effects of the interference terms for soft- and hard-photon emission. The contribution from the emission of a hard photon from the scattered electron should be taken into account. The interference of this term with initial electron and proton emission is also important in leading and next to leading approximation. All these contributions may compensate each other in particular kinematical conditions.

We study the onset of the neutron drip in high-density matter in the presence of a magnetic field. It has been found that, for systems having only protons and electrons, in the presence of a magnetic field $\gtrsim {10}^{15}$ G, neutronization occurs at a density that is at least an order of magnitude higher compared to that in a nonmagnetic system. In a system with heavier ions, the effect of the magnetic field, however, starts arising at a much higher field, $\gtrsim {10}^{17}$ G. These results may have important implications for high-magnetic-field neutron stars and white dwarfs and, in general, in nuclear astrophysics when the system is embedded within a strong magnetic field.

The occurrence of seniority isomers in semimagic nuclei is a clear indication for shell closure. By performing large-scale shell-model calculations in a model space that allows excitations across the $N=82$ neutron and $Z=50$ proton shell gaps, we investigate the isomerism along the $N=82$ isotonic chain. The calculation describes well the properties of the experimentally observed $8^{+}$ isomeric state and the other low-lying states in ${}^{126}\mathrm{Pd},{}^{128}\mathrm{Pd}$, and ${}^{130}\mathrm{Cd}$. We further predict energy levels and $E2$ transitions for ${}^{126}\mathrm{Ru}$ and ${}^{124}\mathrm{Mo}$ as their structure information is necessary for a complete understanding of the seniority picture. Our results, together with other existing evidence, support the conclusion that the shell closure persists at the neutron number $N=82$ in the neutron-rich region.

The formation of the fragments in a reaction is addressed by modifying the minimum spanning tree method by using thermal binding energies. Each fragment is subjected to the fulfillment of thermal binding energy. Our detailed investigation covering different masses, incident energies, and impact parameters indicates a significant role of thermal binding energies over that of cold matter.

We study within the IP-Glasma and two-component MC-Glauber models the effects of initial-state geometry and fluctuations on multiplicities and eccentricities for several collision species at the Relativistic Heavy Ion Collider (RHIC). These include copper-gold (Cu + Au), gold-gold (Au + Au), and uranium-uranium (U + U) collisions. The multiplicity densities per participant pair are very similar in all systems studied. Ellipticities vary strongly between collision systems, most significantly for central collisions, while fluctuation driven odd moments vary little between systems. Event-by-event distributions of eccentricities in mid-central collisions are wider in Cu + Au relative to Au + Au and U + U systems. An anticorrelation between multiplicity and eccentricity is observed in ultracentral U + U collisions which is weaker in the IP-Glasma model than the two-component MC-Glauber model. In ultracentral Au + Au collisions the two models predict opposite signs for the slope of this correlation. Measurements of elliptic flow as a function of multiplicity in such central events can therefore be used to discriminate between models with qualitatively different particle production mechanisms.

We study the transition form factors of the light vector to pseudoscalar mesons as functions of the momentum transfer $q^2$ within the light-front quark model. With these form factors, we calculate the decay branching ratios of all possible modes for $V\to P{\ell }^{+}{\ell }^{-}$ ($V=\omega$ and $\varphi$, $P={\pi }^0$, $\eta$, and ${\eta }^{\prime }$, and $\ell =e$ and $\mu$). We find that our numerical results fit with the data, such as those of $\omega \to {\pi }^0{\ell }^{+}{\ell }^{-}$ and $\varphi \to {\pi }^0{e}^{+}{e}^{-}$ from the NA60 Collaboration and $\varphi \to \eta e^{+}{e}^{-}$ with the Spherical Neutral Detector. We also predict that the branching ratios of $\varphi \to {\pi }^0{\mu }^{+}{\mu }^{-}$, $\omega \to \eta e^{+}{e}^{-}$, $\omega \to \eta {\mu }^{+}{\mu }^{-}$, $\varphi \to \eta {\mu }^{+}{\mu }^{-}$, and $\varphi \to {\eta }^{\prime }{e}^{+}{e}^{-}$ to be around $3.48\times {10}^{-6}$, $3.22\times {10}^{-6}$, $1.81\times {10}^{-9}$, $6.86\times {10}^{-6}$, and $2.97\times {10}^{-7}$, respectively.

We study the role of finite-size effects at the hadron-quark phase transition in a new hybrid equation of state constructed from an ab initio Brückner-Hartree-Fock equation of state with the realistic Bonn-B potential for the hadronic phase and a covariant nonlocal Nambu–Jona-Lasinio model for the quark phase. We construct static hybrid star sequences and find that our model can support stable hybrid stars with an onset of quark matter below $2M_{\odot }$ and a maximum mass above $2.17M_{\odot }$ in agreement with recent observations. If the finite-size effects are taken into account the core is composed of pure quark matter. Provided that the quark vector channel interaction is small, and the finite size effects are taken into account, quark matter appears at densities 2–3 times the nuclear saturation density. In that case the proton fraction in the hadronic phase remains below the value required by the onset of the direct URCA process, so that the early onset of quark matter shall affect on the rapid cooling of the star.

The $\alpha$-decay branch of the $\pi h_{11/2}$ isomer in ${}^{164}\mathrm{Ir}$ has been identified using the GREAT spectrometer. The ${}^{164}\mathrm{Ir}$ nuclei were produced using the ${}^{92}\text{Mo}({}^{78}\text{Kr},p5n){}^{164}\text{Ir}$ reaction and separated in flight using the recoil ion transport unit (RITU) gas-filled separator. The measured $\alpha$-decay energy of $6880\pm 10$ keV allowed the excitation of the $\pi h_{11/2}$ state in ${}^{160}\mathrm{Re}$ to be deduced as $166\pm 14$ keV. The half-life of ${}^{164}\mathrm{Ir}$ was measured with improved precision to be $70\pm 10\mu$s and an $\alpha$-decay branching ratio of $4\pm 2$% was determined. Improved half-life and branching ratio measurements were also obtained for ${}^{165}\mathrm{Ir}$, but no evidence was found for the ground-state decays of either ${}^{164}\mathrm{Ir}$ or ${}^{165}\mathrm{Ir}$.

The paper describes the remeasurement of the half-life of ${}^{229}\mathrm{Th}$ (ground state). The half-life was obtained by the measurement of amount content of ${}^{229}\mathrm{Th}$ in the certified ${}^{229}\mathrm{Th}$ radioactivity standard (SRM 4328C) from the National Institute of Standards and Technology. The measurement was performed by isotope dilution inductively coupled plasma mass spectrometry by using two independent standards for quantification. From the results the ${}^{229}\mathrm{Th}$ half-life is determined to be 7917 years with an expanded uncertainty of 48 years using a coverage factor of $k=2$. The methodology is traceable to the International System of Units, and the calculation complies with the recommendations of the Bureau International des Poids et Mesures for nuclear data evaluation.

The effect of the positive $Q$-value neutron transfer (PQNT) channels on the subbarrier fusion process is still far from a clear understanding and hence is worth further investigation. To this end, we have measured the fusion excitation function for ${}^{32}\mathrm{S}+{}^{94}\mathrm{Zr}$ at energies near and below the Coulomb barrier with rather good accuracy, and deduced the experimental fusion barrier distribution. The reaction system ${}^{32}\mathrm{S}+{}^{94}\mathrm{Zr}$ is a good candidate for the evaluation of PQNT effect because it has multineutron transfer channels with positive ground-state $Q_{xn}$ values as well as the relatively weak low-lying $3^{-}$ vibrational state in ${}^{94}\mathrm{Zr}$. Our results show that the fusion cross sections of ${}^{32}\mathrm{S}+{}^{94}\mathrm{Zr}$ are strongly enhanced at the lower-energy region. By means of a cross comparison of the ${}^{32}\mathrm{S}$,${}^{40}\mathrm{Ca}+{}^{90,94,96}\mathrm{Zr}$ systems, further evidence is given that the positive $Q_{xn}$-value neutron transfer channels, rather than the strong low-lying $3^{-}$ vibrational state, bring about the additional subbarrier fusion enhancement. Relative to the coupled-channels results with couplings to the low-lying inelastic collective excitations, an unexpectedly large enhancement for the subbarrier fusion cross sections is observed in ${}^{32}\mathrm{S}+{}^{94}\mathrm{Zr}$ compared to ${}^{32}\mathrm{S}+{}^{96}\mathrm{Zr}$. Some existing theoretical models have been discussed, but a good explanation cannot be achieved. Exact coupled-channels theory and more experiments on transfer reactions themselves are strongly desired to comprehensively understand the effect of transfer on fusion.

To explore the strength, isospin dependence, and density dependence of the in-medium spin-orbit coupling that is poorly known but relevant for understanding the structure of rare isotopes, the nucleon spin up-down differential transverse flow is studied systematically by varying the beam energy and impact parameter of $\mathrm{Au}+\mathrm{Au}$ collisions within a spin-isospin-dependent transport model recently developed for investigating spin-related phenomena in intermediate-energy heavy-ion collisions. The optimal reaction conditions for delineating and disentangling effects of different terms in the spin-orbit coupling are discussed.

Cross sections of the ${}^{57}{\text{Fe}(n,\alpha )}^{54}$Cr reaction are measured for the first time, and those of the ${}^{63}\text{Cu}(n,\alpha {)}^{60}\text{Co}$ reaction are measured in the megaelectron volt region by the direct experimental method. Experiments were performed at the 4.5-MV Van de Graaff Accelerator of Peking University. Monoenergetic neutrons (5.0, 5.5, 6.0, and 6.5 MeV) were produced through the ${}^2$H($d,n$)${}^3$He reaction with a deuterium gas target. Measurements were carried out using a double-section-gridded ionization chamber and back-to-back double ${}^{57}$Fe and ${}^{63}$Cu samples. Foreground and background were measured in separate runs. A ${}^{238}$U sample and a BF${}_3$ long counter were utilized for absolute neutron flux calibration and for neutron flux normalization, respectively. Present results are compared with talys-1.4 code predictions, existing measurements, and evaluations.

We test the effects of an approximate treatment of two-body contributions to the axial-vector current on the quasiparticle random-phase approximation (QRPA) matrix elements for neutrinoless double-beta decay in a range of isotopes. The form and strength of the two-body terms come from chiral effective-field theory. The two-body currents typically reduce the matrix elements by about 20%, not as much as in shell-model calculations. One reason for the difference is that standard practice in the QRPA is to adjust the strength of the isoscalar pairing interaction to reproduce two-neutrino double-beta decay lifetimes. Another may be the larger QRPA single-particle space. Whatever the reasons, the effects on neutrinoless decay are significantly less than those on two-neutrino decay, both in the shell model and the QRPA.