The medium modifications of the open charm mesons ($D$ and $\overline{D}$) are studied in isospin asymmetric nuclear matter in the presence of strong magnetic fields, using a chiral effective model. The mass modifications of these mesons in the effective hadronic model arise due to their interactions with the protons, neutrons, and the scalar mesons (nonstrange isoscalar, $\sigma$, strange isoscalar, $\zeta$, and nonstrange isovector, $\delta$) in the magnetized nuclear matter. In the presence of a magnetic field, for the charged baryon, i.e., the proton, the number density as well as the scalar density have contributions due to the summation over the Landau energy levels. For given values of the baryon density and isospin asymmetry, the scalar fields are solved self-consistently from their coupled equations of motion. The modifications of the masses of the $D$ and $\overline{D}$ mesons are calculated from the medium modifications of the scalar fields and the nucleons. The effects of the anomalous magnetic moments of the nucleons on the masses of the open charm mesons are also investigated in the present work. The effects of isospin asymmetry as well as of the anomalous magnetic moments are observed to be prominent at high densities for large values of magnetic fields.

Isotopes with low-lying long-lived isomers can behave very differently from other isotopes in astrophysical environments. In particular, the assumption of thermal equilibrium in computing the temperature-dependent $\beta$-decay rates of such isotopes can fail below certain temperatures. We focus on the $\beta$ decay of ${}^{26}\mathrm{Al}$ since it is one of the most important isotopes in observational astrophysics and has a low-lying isomeric state; we compare and contrast these results with ${}^{34}\mathrm{Cl}$. We rule out recently reported ${}^{26}\mathrm{Al}$ effective $\beta$-decay rates that showed large differences from previous calculations, finding that we agree with the earlier results. We conclude that in general, effective $\beta$-decay rates should be defined separately for the ground and isomeric states at temperatures where thermal equilibrium cannot be achieved.

The probabilities of α decay and heavy-cluster decay in the superheavy region are investigated. The preformation probabilities for α and cluster emissions are evaluated with a new formula which depends on the $Q$ value of the decay. The formula shows a better agreement with the experimentally extracted cluster preformation probabilities in the heavy region. The α half-lives using our model are compared with the experimental results and it is found that the present model can be employed successfully to predict α half-lives in the superheavy region. The probable heavy-cluster radioactivity from superheavy nuclei is also studied using the same model. A comparison of the heavy-cluster half-lives using the present model, the half-lives given by Poenaru et al. [Eur. Phys. J. A 54, 14 (2018)] (analytical superasymmetric fission) and Zhang et al. [Phys. Rev. C 97, 014318 (2018)] are performed. The agreement between these three formalisms is evident from the study. A further study on the competition between α decay and heavy-cluster radioactivity leading to ${}^{208}\mathrm{Pb}$ is performed. The study suggests that heavy-cluster radioactivity may be comparable to or even dominant over α decay for some of the isotopes with $Z\ge 118$. The study shows that the present model can be used effectively to obtain the α as well as the heavier cluster decay half-lives in the superheavy region.

The ${}^{70}\mathrm{Zn}\left(n,\gamma \right){}^{71}\mathrm{Z}{\mathrm{n}}^{\mathrm{m}}$ ($T_{1/2}=3.96\mathrm{h}$) cross section has been measured at $0.40\pm 0.15\mathrm{MeV}$ and $0.70\pm 0.10\mathrm{MeV}$ using a ${}^7\mathrm{Li}{\left(p,n\right)}^7\mathrm{Be}$ neutron source. The energy of proton energy of neutron energy spectrum code was used to calculate the neutron energy spectrum, and the ${}^{197}\mathrm{Au}{\left(n,\gamma \right)}^{198}\mathrm{Au}$ reaction was used as monitor reaction. Detailed uncertainty analysis has been performed, and the newly measured cross sections are reported with their uncertainties and correlation coefficients. The energy dependence seen in the cross sections measured in the present work and in the previous work at higher energies has been compared with the theoretical model prediction with various level density models and γ-ray strength functions. Model code dependence of the prediction is also discussed.

The production of the heaviest elements in fusion-evaporation reactions is substantially limited by very low cross sections, as fusion cross sections (including fusion-fission) are greatly reduced by the competing quasifission mechanism. Using the Australian National University Heavy Ion Accelerator Facility and CUBE detector array, fission fragments from the ${}^{48}\mathrm{Ti}+{}^{204,208}\mathrm{Pb}$ and ${}^{50}\mathrm{Ti}+{}^{206,208}\mathrm{Pb}$ reactions have been measured, with the aim to investigate how the competition between quasifission and fusion-fission evolves with small changes in entrance-channel properties associated mainly with the nuclear structure. Analysis of mass-distribution widths of strongly mass-angle-correlated fission fragments within the framework of the compound-nucleus fission theory demonstrates significant differences in quasifission (and therefore fusion) probabilities among the four reactions. The impact of nuclear structure on fusion highlights the importance of future radioactive beams.

We calculate $\mathrm{\Lambda }$ and $\overline{\mathrm{\Lambda }}$ hadron production cross sections in charged lepton semi-inclusive deep-inelastic scattering off nuclear target ($A$, using iron $\mathrm{Fe}$ as an example) and deuteron ($D$) target. The results show that the ratio $({\overline{\mathrm{\Lambda }}}^A/{\mathrm{\Lambda }}^A)/({\overline{\mathrm{\Lambda }}}^D/{\mathrm{\Lambda }}^D)$ is sensitive to the sea quark content of the nucleus. We adopt three different models to take the nuclear EMC effect into account. The ratio $({\overline{\mathrm{\Lambda }}}^A/{\mathrm{\Lambda }}^A)/({\overline{\mathrm{\Lambda }}}^D/{\mathrm{\Lambda }}^D)$ is predicted to be different by these different models.

The effective field theory (EFT) for triaxially deformed even-even nuclei is generalized to include the vibrational degrees of freedom. The pertinent Hamiltonian is constructed up to next-to-leading order (NLO). The leading-order part describes the vibrational motion, and the NLO part couples rotations to vibrations. The applicability of the EFT Hamiltonian is examined through the description of the energy spectra of the ground state bands, $\gamma$ bands, and $K=4$ bands in the ${}^{108,110,112}\mathrm{Ru}$ isotopes. It is found that, by taking into account the vibrational degrees of freedom, the deviations for high-spin states in the $\gamma$ band observed in the EFT with only rotational degrees of freedom disappear. This supports the importance of including vibrational degrees of freedom in the EFT formulation for the collective motion of triaxially deformed nuclei.

The observed shears bands in ${}^{198}\mathrm{Pb}$ and ${}^{199}\mathrm{Pb}$ are investigated within the framework of tilted axis cranking covariant density functional theory, and the separable pairing force is adopted to consider the pairing correlations. The energy spectra, total angular momenta, and transition probabilities agree well with the experimental data. The bandhead energy differences are reproduced satisfactorily without any ad hoc renormalizations when the pairing correlations are taken into account. The angular momentum vectors are discussed in detail to analyze the pairing effects on magnetic rotations.

Studies of fluctuations and correlations of soft hadrons and hard and electromagnetic probes of the dense and strongly interacting medium require event-by-event hydrodynamic simulations of high-energy heavy-ion collisions that are computing intensive. We develop a $\left(3+1\right)$-dimensional viscous hydrodynamic model—CLVisc that is parallelized on a graphics processing unit (GPU) by using the open computing language (OpenCL) with 60 times performance increase for spacetime evolution and more than 120 times for the Cooper–Frye particlization relative to that without GPU parallelization. The model is validated with comparisons with different analytic solutions, other existing numerical solutions of hydrodynamics, and experimental data on hadron spectra in high-energy heavy-ion collisions. The pseudorapidity dependence of anisotropic flow $v_n\left(\eta \right)$ are then computed in CLVisc with initial conditions given by the a multiphase transport (ampt) model, with energy density fluctuations both in the transverse plane and along the longitudinal direction. Although the magnitude of $v_n\left(\eta \right)$ and the ratios between $v_2\left(\eta \right)$ and $v_3\left(\eta \right)$ are sensitive to the effective shear viscosity over entropy density ratio ${\eta }_v/s$, the shape of the $v_n\left(\eta \right)$ distributions in $\eta$ do not depend on the value of ${\eta }_v/s$. The decorrelation of $v_n$ along the pseudorapidity direction due to the twist and fluctuation of the event planes in the initial parton density distributions is also studied. The decorrelation observable $r_n({\eta }^a,{\eta }^b)$ between $v_n\{-{\eta }^a\}$ and $v_n\left\{{\eta }^a\right\}$ with the auxiliary reference window ${\eta }^b$ is found not to be sensitive to ${\eta }_v/s$ when there is no initial fluid velocity. For small ${\eta }_v/s$, the initial fluid velocity from mini-jet partons introduces sizable splitting of $r_n({\eta }^a,{\eta }^b)$ between the two reference rapidity windows ${\eta }^b\in [3,4]$ and ${\eta }^b\in [4.4,5.0]$, as has been observed in experiment. The implementation of CLVisc and guidelines on how to efficiently parallelize scientific programs on GPUs are also provided.

We study the long-wavelength excitations of the inner crust of neutron stars, considering three phases: cubic crystals at low densities, and rods and plates near the core-crust transition. To describe the phonons, we write an effective Lagrangian density in terms of the coarse-grained phase of the neutron superfluid gap and of the average displacement field of the clusters. The kinetic energy, including the entrainment of the neutron gas by the clusters, is obtained within a superfluid hydrodynamics approach. The potential energy is determined from a model where clusters and neutron gas are considered in phase coexistence, augmented by the elasticity of the lattice due to Coulomb and surface effects. All three phases show strong anisotropy, i.e., angle dependence of the phonon velocities. Consequences for the specific heat at low temperature are discussed.

The fusion reaction ${}^{12}\mathrm{C}({}^{12}\mathrm{C},\mathrm{p}){}^{23}\mathrm{Na}$ has been studied from $E=2.00$ to 4.00 MeV by particle spectroscopy. The data reveal broad resonances above $E=3.00$ MeV and are compatible with previously reported resonance structure around $E=2.1$ MeV. The data were limited at low energies by low count rates as well as possible background contributions. This experiment extends the previously achieved low-energy measurement by charged particle spectroscopy to 2 MeV, which corresponds to the high-energy side of the astrophysically relevant temperature. Present knowledge of level structures and nonresonant contribution cannot explain the results of the present experiment, which may change the ${}^{12}\mathrm{C}+{}^{12}\mathrm{C}$ reaction rate significantly. Despite the progress decreasing the low-energy limit, any extrapolation into the astrophysical energy range remains highly uncertain based on available experimental data.

The claim of Tanabe and Sugawara-Tanabe [Phys. Rev. C 95, 064315 (2017)] that transverse wobbling is unstable is contradicted. Examples for stable transverse wobbling are provided. It is demonstrated that the alternative scenario suggested in the commented paper violates fundamental properties of the nuclear many-body system.

We reply to the preceding Comment.

We report on two complementary delayed gamma-ray spectroscopic studies on ${}_{64}{}^{164}\mathrm{Gd}_{100}$. The nucleus is produced via spontaneous fission of ${}^{252}\mathrm{Cf}$ sources used in selective experimental setups. An isomeric state at 1095 keV with a half-life of 605 (30) ns is confirmed as well as its decay path toward the ground state band. From comparison to other $N=100$ isotones and with calculations based on the axially symmetric-deformed quasiparticle random phase approximation (QRPA) using the up-to-date Gogny interaction a $4^{-}$ spin and parity is proposed for the isomer. The state is interpreted as a two-quasi-neutron excitation in line with available data for others $N=100$ isotones. The variation of the lifetime of the isomeric state along the $N=100$ isotones is interpreted in terms of Coriolis mixing implemented for the first time within axially symmetric-deformed QRPA microscopic calculations.

The previous mean-field calculation [Phys. Rev. C 78, 054311 (2008)] has shown that the oblate deformation in ${}^{28,30,32}\mathrm{Si}$ disappears when a $\mathrm{\Lambda }$ particle is added to these nuclei. Here, we investigate this phenomenon by taking into account the effects beyond the mean-field approximation. To this end, we employ the microscopic particle-rotor model based on the covariant density functional theory. We show that the deformation of ${}^{30}\mathrm{Si}$ does not completely disappear, even though it is somewhat reduced, after a $\mathrm{\Lambda }$ particle is added if the beyond-mean-field effect is taken into account. We also discuss the impurity effect of a $\mathrm{\Lambda }$ particle on the electric-quadrupole transition and show that an addition of a $\mathrm{\Lambda }$ particle leads to a reduction in the $B\left(E2\right)$ value, as a consequence of the reduction in the deformation parameter.

Calculations of the direct radiative capture reactions are made for the ${}^{48}\mathrm{Ca}(n,\gamma ){}^{49}\mathrm{Ca}$, ${}^7\mathrm{Li}(n,\gamma ){}^8\mathrm{Li}$, and ${}^{12}\mathrm{C}(p,\gamma ){}^{13}\mathrm{N}$ reactions with the Perey-Buck-type nonlocal potentials using a potential model. Our results reproduce the experimental data reasonably well. From comparisons to results obtained by using local potentials, it is found that the cross sections of direct capture reactions may change by around 25% due to the nonlocality of nuclear potentials.

The directed flow ($v_1$) of open charm meson ($D^0$) is studied in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV using a multiphase transport model framework with partonic interactions (string melting version). Within this framework, it is found that although the initial spatial eccentricity (${\epsilon }_1$) of charm quark is smaller than light quarks, the charm quark $v_1$ magnitude is found to be approximately seven times larger than that of the light $u$ quark at large rapidity. This indicates that the charm quarks can retain more information from initial condition than the light quarks. We have studied the directed flow of $D^0$ as a function of rapidity and transverse momentum using quark coalescence as the mechanism for hadron production. Like the charm quark, the $D^0{v}_1$ magnitude is found to be about seven times larger than that of the light ($\pi$) hadrons at large rapidity.

As suggested in a Comment by Peters [Phys. Rev. C 96, 029801 (2017)], a correction is applied to the ${}^{13}\mathrm{C}(\alpha ,n){}^{16}\mathrm{O}$ data of Harissopulos et al. [Phys. Rev. C 72, 062801(R) (2005)]. The correction refers to the energy-dependent efficiency of the neutron detector and appears only above the ($\alpha ,n_1$) threshold of the ${}^{13}\mathrm{C}(\alpha ,n){}^{16}\mathrm{O}$ reaction at about $E_{\alpha }\approx 5$ MeV. The corrected data are lower than the original data by almost a factor of 2. The correction method is verified using recent neutron spectroscopy data and data from the reverse ${}^{16}\mathrm{O}(n,\alpha ){}^{13}\mathrm{C}$ reaction.

Several zirconium isotopes are in the path of slow neutron capture (s) process, and the direct components of ($n,\gamma$) reactions can be derived from their neutron spectroscopic factors. In the present work, the angular distributions of (${}^{12}\mathrm{C},{}^{13}\mathrm{C}$) and (${}^{13}\mathrm{C},{}^{12}\mathrm{C}$) reactions on targets ${}^{90,92,94,96}\mathrm{Zr}$ were obtained using the high-precision Q3D magnetic spectrograph at the Beijing HI-13 tandem accelerator in China Institute of Atomic Energy. The distorted-wave Born approximation calculations were performed to extract the spectroscopic factors, using three different sets of Woods-Saxon potential parameters for these heavy-ion systems. The neutron spectroscopic factors for the ground state of ${}^{90–97}\mathrm{Zr}$ have been obtained and compared with other experimental data.