For even–even nuclei ^180−184Yb, ^182−186Hf and ^184−188W located on an island of hexadecapole-deformation archipelago, the structure properties, especially under rotation, are reinvestigated by using the Hartree–Fock–Bogliubov–Cranking (HFBC) calculation with a fixed shape (e.g., the ground-state equilibrium shape). The equilibrium deformations, extracted from the potential energy surface, are calculated based on the phenomenological Woods–Saxon (WS) mean-field Hamiltonian within the framework of macroscopic-microscopic (MM) model. The impact of different deformation degrees of freedom on, e.g., single-particle levels, total energy, and moment of inertia (MoI), is revealed, especially concentrating on the hexadecapole-deformation effects and the quadrupole-hexadecapole coupling. Considering the axially hexadecapole deformation, the present calculations can reproduce available experimental data well, including the quadrupole deformations and moments of inertia. Interestingly, it is found that the impact of different deformation degrees of freedom on MoI exhibits a similar trend in the HFBC and rigid-body calculations though the latter ignores the pairing effects. Before starting or constructing a complex theory-model, to some extent, such a similarity can provide an alternative way of understanding the effect of, e.g., exotic deformations, on the MoI by the calculation of a simple rigid-body approximation. The present findings could offer insights into the static and dynamic effects of hexadecapole deformations, contributing valuable information for the corresponding research in nuclear structure and reaction.

This work provides an analysis of p_T spectra for identified hadrons generated during gold–gold collisions at a center-of-mass energy ($\sqrt{{s}_{NN}}$) of 11.5 GeV. The data, recorded by the STAR detector at the Relativistic Heavy Ion Collider, is evaluated using predictions from phenomenological models. Specifically, we compare the outcomes of Monte Carlo simulations from Pythia 8.3 and EPOS (comprising EPOS4 and EPOSLHC) with experimental observations. Our investigation focuses on π^±, K^±, and (anti-)proton spectra measured at mid-rapidity (∣y∣ < 0.1) across nine distinct centrality classes. In the case of π^±, EPOS4 model shows good agreement with the data only in the low p_T region. However, it successfully reproduces the results across the entire p_T range for the last three centrality classes for pions yields. In the case of K^±, EPOS4 exhibit good agreement with the experimental data. For proton and (anti-)proton, this model mostly underestimates in high-p_T region, likely due to the reduced interaction volume and lower rescattering probability. In contrast, Pythia 8.3 often overpredicts pion yields and provides consistent representations for kaons and for (anti-)protons, Pythia 8.3 and EPOSLHC fails to describe the data. Pythia 8.3 mostly overestimates the data in the case of proton. EPOS4 demonstrates a good description of pion spectra compared to Pythia 8.3, largely attributable to its inclusion of hadronic rescattering effects. Meanwhile, EPOSLHC shows better alignment with experimental data in the case of kaons and proton for the entire p_T range while for pions it also better reproduced the result at higher p_T only. At higher p_T, EPOSLHC exhibits a suppression relative to the experimental data, indicating limitations of the model description in a momentum region where collective flow effects are expected to be minimal. EPOS4 and EPOSLHC outperform Pythia 8.3, primarily due to their ability to incorporate correlated flow dynamics and hadronic rescattering effects. In contrast, Pythia 8.3 lacks these mechanisms, leading to less precise spectral descriptions. None of the models accurately replicate the experimental data for the (70–80)% centrality class likely due to the absence of collective effects and the increased role of non-equilibrium dynamics in these events. Additionally, the extracted freeze-out parameters indicate a rise in effective temperature and a decrease in the non-extensive parameter with increasing centrality. These trends suggest greater system excitation and more rapid thermal equilibration in highly central collisions.

The electronic stopping power of magnesium (Mg) for protons is studied over a wide range of velocities by performing real-time time-dependent density functional theory (TDDFT) simulations. The electronic stopping power of Mg for high-velocity protons traveling along both channeling and off-channeling trajectories is calculated, and the microscopic mechanism responsible for the inner-electron excitation of Mg is revealed. In the low-velocity range (v < 1 au), the stopping power calculated from the channeling geometry aligns closely with the experimental measurements. It captures the departure from the linear relationship between the stopping power and proton velocity, which is attributed to charge exchange effect between protons and host electrons. The threshold velocities for 2p and 2s electron excitation of Mg for protons were found by TDDFT calculations. In the high-velocity range, the dependence of 2s-electron excitation on the impact parameter was investigated. Compared to channeling stopping, the off-channeling stopping exhibits significant enhancement. Furthermore, the impact of ion trajectories on electron excitation was also investigated. The results confirmed that the 3s electron excitation makes a significant contribution, and the decrease of the impact parameter enhances the inner electron excitation.

A physics-informed neural network (PINN) is built to solve the nucleonic Dirac equation. The PINN employs the residual of the Dirac equation as the objective function instead of the variation of the energy expectation value, thereby avoiding the variational collapse problem. By integrating the automatic differentiation techniques, the PINN also overcomes the Fermion doubling problem. A constraint term in the loss function of the PINN is designed to avoid trivial solutions and an orthogonality constraint term is used to search for the excited states. The performance of the unsupervised PINN is evaluated by solving the orbitals below the Fermi surface of ¹⁶O and ²⁰⁸Pb in the Dirac Woods-Saxon (WS) potential. Compared to the results obtained by the traditional shooting method, obtained energies have relative errors on the order of 10^-3 and the root-mean-square errors of the corresponding wave functions are also on the order of 10^-3.

In the present work, based on the Wentzel-Kramers-Brillouin approximation and Bohr-Sommerfeld quantization condition, we extend a phenomenological modified harmonic oscillator potential model proposed by Bayrak [J. Phys. G 47: 025102, 2020] to systematically investigate the favored proton radioactivity by considering the spectroscopic factors S_p from the relativistic mean-field theory and the Bardeen-Cooper-Schrieffer method. Calculations show good agreement with experimental data within a factor of 2.7. Furthermore, employing this model, we predict the proton radioactivity half-lives of potential candidates that are energetically allowed or observed but not yet quantified in the latest atomic mass excess NUBASE2020. For comparison, the one-parameter model [Commun. Theor. Phys. 74: 115302, 2022] and the universal decay law [Phys. Rev. C 85: 011303, 2012] are also employed. All the corresponding predictions are consistent with each other. In addition, the reliability of our predictions is further confirmed by comparing the simple formula proposed by Delion et al [Phys. Rev. Lett. 96: 072501, 2006] and the new Geiger-Nuttall law put forward by Chen et al [Eur. Phys. J. A 55: 214, 2019].

The probabilities of forming an α-particle at the surface of heavy nuclei (spectroscopic factors) in the states of different angular momenta are calculated within the dinuclear system (DNS) approach. It is shown that this dependence is determined not only by the energies of the excited states of the daughter nucleus, as is suggested by the Boltzmann distribution, but also by its quadrupole and octupole deformation parameters. If the daughter nucleus is almost spherical, in the course of α-decay, it is predominantly populated in the ground state, whereas the population of other yrast states is strongly suppressed. If the daughter nucleus possesses quadrupole deformation but negligible octupole deformation, the states with even angular momenta are primarily populated. To populate the states with odd angular momenta, the daughter nucleus should be octupole deformed. The dependence of spectroscopic factors on the angular momentum of the daughter nucleus was calculated for actinide nuclei ^222-228Ra, ^222-232Th, ^226-236U, and ^234-242Pu. The results obtained will be useful in future studies on the fine structure of α-decay.

The study of nuclear isomers can deepen our understanding of nuclear structure and astrophysics. In this work, we have performed the ab initio calculations of isomers in the N = 49 isotones. With a chiral two- plus three-nucleon force, the valence-space effective Hamiltonian was derived using the ab initio many-body perturbation theory named $\hat{Q}$-box folded diagrams. The effective operators of electromagnetic operators and β-decay were obtained using $\hat{{\rm{\Theta }}}$-box folded diagrams. With the effective Hamiltonian and operators, we studied the properties of the isomers, gaining a microscopic understanding of the single-particle behaviour of the isomers which we are interested in, showing the reliability of the ab initio calculations.

In this work, we investigate the strong decays for P-wave excited states of doubly charmed and bottom baryons in the constituent quark model. Our results indicate that some λ-mode Ξ_cc/bb(1P) and Ω_cc/bb(1P) states are relatively narrow, which are very likely to be discovered by future experiments. The light meson emissions for the low-lying ρ-mode states are highly suppressed due to the orthogonality of wave functions between initial and final states. Moreover, the strong decay behaviors for doubly charmed and bottom baryons preserve the heavy superflavor symmetry well, where the small violation originates from the finite heavy quark masses. We hope that present theoretical results for undiscovered doubly charmed and bottom baryons can provide helpful information for future experiments and help us to better understand the heavy quark symmetry.

White dwarfs, one of the compact objects in the Universe, play a crucial role in astrophysical research and provide a platform for exploring nuclear physics. In this work, we extend the relativistic mean field approach by using a Walecka-type quantum hadrodynamics model to capture the intricate structure of white dwarfs. We calculate nuclear properties, Coulomb energy, and photon energy within white dwarfs in a unified framework. By carefully calibrating the model parameters to align with nuclear matter properties, we successfully reproduce the structures of several elements in white dwarfs, such as the isotopes of C and ¹⁶O, except for the unnaturally deeply bound state ⁴He. Furthermore, we predict the characteristics of white dwarfs composed of atom-like units and the gravitational waves stemming from binary white dwarf inspirals incorporating tidal deformability contributions up to the 2.5 post-Newtonian order. These results shed light on the structure of white dwarfs and provide valuable information for future gravitational wave detection. This methodological advancement allows for a cohesive analysis of white dwarfs, neutron stars, and the nuclear pasta within a unified theoretical framework.

The observed identical π7/2⁻[514] band and near-identical π1/2⁻[521] band in ²⁵¹Md and ²⁵⁵Lr are investigated using the cranked shell model (CSM) with the particle-number-conserving (PNC) pairing method. The experimental kinematic moments of inertia (MOIs) J⁽¹⁾ for each band are reproduced well by the PNC-CSM calculations. A remarkable identity is exhibited for the variation of the calculated MOIs J⁽¹⁾ versus the frequency between ²⁵¹Md and ²⁵⁵Lr, which is attributed to the identical contributions of the alignment from the blocked proton orbitals π[514]7/2 (π[521]1/2) in ²⁵¹Md and ²⁵⁵Lr. The slight differences of J⁽¹⁾ at high frequency ℏω > 0.2 MeV for the near-identical π1/2⁻[521] band are due to the contributions of the direct term j⁽¹⁾(μ) and the interference term j⁽¹⁾(μν) based on the neutron orbital ν9/2⁻[734]. The B(E2) values are lower in ²⁵¹Md than in ²⁵⁵Lr while the pairing gaps are almost the same for the π7/2⁻[514] and π1/2⁻[521] bands. The behaviors of the B(E2) values (pairing gaps) versus frequency are predicted to exhibit a remarkable similarity in ²⁵¹Md and ²⁵⁵Lr.

Inspired by the profoundly observed odd–even staggering and the inverted parabolic-like shape in charge radii along calcium isotopic chain, the ground state properties of calcium isotopes are investigated by constraining the root-mean-square charge radii under the covariant energy density functionals with effective forces NL3 and PK1. In this work, the pairing correlations are tackled by solving the state-dependent Bardeen–Cooper–Schrieffer equations. The calculated results suggest that the binding energies obtained by the radius constraint method have been slightly changed by about 0.2%. But for charge radii, the corresponding results deriving from NL3 and PK1 forces have been increased by about 1.0% and 2.0%, respectively. This means that the charge radius is a more sensitive quantity in the calibrated protocol. Meanwhile, it is found that the reproduced charge radii of calcium isotopes are attributed to the rather strong isospin dependence of effective potential. The odd–even oscillation behavior can also be presented in the proton Fermi energies along calcium isotopic family, but keep opposite trends with respect to the corresponding binding energies and charge radii. As encountered in charge radii, the weakened odd–even oscillation behavior still emerged from the proton Fermi energies at the neutron numbers N = 20 and 28 as well, but not in binding energies.

This work demonstrates that once a large number of pion is condensed in a high-energy hadron collision, the gamma-ray spectrum from π⁰ decay takes on a typical broken power-law shape, which has been documented in many astronomical observations, but we have not yet recognized it. We show that this pion condensation is caused by a large number of soft gluons condensed in protons.

The β-decay properties of ⁶⁷⁻⁸⁰As nuclei have been investigated within the framework of the proton–neutron quasi-particle random phase approximation (pn-QRPA) model. The nuclear deformation obtained from the finite range droplet model is used as an input parameter in the pn-QRPA model for the analysis of β-decay properties including Gamow–Teller strength distributions, log ft, β-decay half-lives and stellar β^± decay rates. The predicted log ft values were fairly consistent with the observed data. The computed β-decay half-lives matched the measured values by a factor of 10. The stellar rates were compared with the shell model outcomes. At high densities and temperatures, the β⁺ and electron capture rates had a finite contribution. However, the β⁻ and positron capture rates are only significant at high temperatures and low densities. The pn-QRPA rates outperformed the shell model rates by a factor of 22 or more.

The fusion excitation functions for 12 colliding systems with 96 ≤ Z₁Z₂ ≤ 608 are analyzed using coupled-channel (CC) calculations based on the M3Y double-folding (DF) potential supplemented with a repulsive potential that takes into account the incompressibility of the nuclear matter. We also applied the polarization effects of hot nuclear matter (PEHNM) on the calculations of the bare nucleus–-nucleus interaction potential within the framework of the modified density-dependent Seyler–Blanchard (SB) approach in the T² approximation. Our results reveal that we obtain a nice description of the experimental data of different fusion systems when we use the present theoretical approach to calculate the energy-dependent values of the fusion cross sections. In this paper, the influence of the PEHNM on the surface diffuseness parameter of the Woods–Saxon (WS) potential is also studied. In order to reach this goal, we extract the corresponding values of this parameter based on the modified form of the DF potential (M3Y+Repulsion+polarization). We find that the extracted values are located in a range between a = 0.61 and 0.80 fm at different incident energies. It seems that the polarization effects of hot nuclear matter play a key role in describing the abnormally large values of the nuclear potential diffusenesses in the heavy-ion fusion reactions. Additionally, the regular decreasing trend for the diffuseness parameter of the nucleus–nucleus potential with the increase in the bombarding energies is also observed.

This study endeavors to develop an improved set of basis functions for nuclear shell-model calculations. The shell model, a well-established approach to understanding nuclear structure, typically employs the harmonic oscillator potential within the mean-field approximation. Given the extensive validation and consistency of harmonic oscillator results with experimental data, we propose a modification by incorporating a centrifugal term that converges toward the Davidson potential. This potential has been extensively studied, and we aim to extract relevant experimental data for the simplest cases in the shell model, namely one-particle and one-hole nuclei. A comprehensive comparison between the Davidson-based results and the harmonic oscillator calculations is presented to demonstrate the effectiveness of the new basis functions.

The Schrodinger equation with a Yukawa type of potential is solved analytically. When different boundary conditions are taken into account, a series of solutions are indicated as a Bessel function, the first kind of Hankel function and the second kind of Hankel function, respectively. Subsequently, the scattering processes of $K{\bar{K}}^{* }$ and $D{\bar{D}}^{* }$ are investigated. In the $K{\bar{K}}^{* }$ sector, the f₁(1285) particle is treated as a $K{\bar{K}}^{* }$ bound state, therefore, the coupling constant in the $K{\bar{K}}^{* }$ Yukawa potential can be fixed according to the binding energy of the f₁(1285) particle. Consequently, a $K{\bar{K}}^{* }$ resonance state is generated by solving the Schrodinger equation with the outgoing wave condition, which lies at 1417 − i18 MeV on the complex energy plane. It is reasonable to assume that the $K{\bar{K}}^{* }$ resonance state at 1417 − i18 MeV might correspond to the f₁(1420) particle in the review of the Particle Data Group. In the $D{\bar{D}}^{* }$ sector, since the X(3872) particle is almost located at the $D{\bar{D}}^{* }$ threshold, its binding energy is approximately equal to zero. Therefore, the coupling constant in the $D{\bar{D}}^{* }$ Yukawa potential is determined, which is related to the first zero point of the zero-order Bessel function. Similarly to the $K{\bar{K}}^{* }$ case, four resonance states are produced as solutions of the Schrodinger equation with the outgoing wave condition. It is assumed that the resonance states at 3885 − i1 MeV, 4029 − i108 MeV, 4328 − i191 MeV and 4772 − i267 MeV might be associated with the Zc(3900), the X(3940), the χ_c1(4274) and χ_c1(4685) particles, respectively. It is noted that all solutions are isospin degenerate.

The role of the delta isobar degrees of freedom in nucleon–nucleon scattering is revisited. We attempt to understand why the dimensionally regularized two-pion exchanges with the explicit delta isobar is much stronger than the ones with spectral function regularization. When the cut-off value of spectral function regularization is varied, the isoscalar central component exhibits a rather large cut-off variation. This reveals a surprisingly large numerical factor of the deltaful two-pion exchange potentials. The power counting is adjusted accordingly and we discuss the results and how to improve upon this finding.

The structure of the irreducible collective spaces of the group Sp(12, R), which many-particle nuclear states are classified according to the chain Sp(12, R) ⊃ U(6) ⊃ SO(6) ⊃ SU_pn(3) ⨂ SO(2) ⊃ SO(3) of the proton–neutron symplectic model (PNSM), is considered in detail. This chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr–Mottelson collective model. The construction of the relevant shell-model representations of the Sp(12, R) group along this chain is considered for three nuclei with varying collective properties and from different mass regions. It is shown that the SU_pn(3) basis states of the Sp(12, R) representations belonging to the SO(6) irreps with seniority $\upsilon$ ≥ $\upsilon$₀, with $\upsilon$₀ denoting the maximal seniority SO(6) irrep contained in the Sp(12, R) bandhead, are always Pauli allowed, but organized in a different way into different SO(6) shells. This is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm operation. Although the SU_pn(3) multiplets within $\upsilon$ < $\upsilon$₀ are not all Pauli forbidden, it is safe to discard them. The results obtained in the present work are important for the practical application of the microscopic version of the Bohr–Mottelson collective model.

By using potential energy surface (PES) calculations in the three-dimensional space (β₂, γ, β₄) within the framework of the macroscopic-microscopic model, the fission trajectory and fission barrier for Z = 118(Og), 119, 120 nuclei has been systematically investigated. The calculated PES includes macroscopic liquid-drop energy, microscopic shell correction and pairing correction. Taking the ²⁹⁴Og₁₇₆ nucleus as an example, we discuss the next closed shell after Z = 82 and N = 126 with the calculated Woods–Saxon single-particle levels. Then, the results of PES in ²⁹⁴Og is illustrated from the (X, Y) scale to the (β₂, γ) scale. The γ degree of freedom reveals the shape evolution clearly during the fission process. The structure near the minimum and saddle point of the PES in the Z = 118, 119, 120 nuclei is demonstrated simultaneously. Based on the potential energy curves, general trends of the evolution of the fission barrier heights and widths are also studied. The triaxial deformation in these superheavy mass regions plays a vital role in the first fission barrier, showing a significant reduction in both triaxial paths. In addition, the model-dependent fission barriers of proton-rich nuclei ²⁹⁵Og, ²⁹⁶119, and ²⁹⁷120 are analyzed briefly. Our studies could be valuable for synthesizing the superheavy new elements in the forthcoming HIAF and other facilities.

The fusion barriers and cross sections of 15 colliding systems with 320 ≤ Z₁Z₂ ≤ 1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion mechanism. To realize this goal, we select three versions of the phenomenological proximity potentials, including Prox. 77, Zhang 2013, and Guo 2013, to calculate the nucleus–nucleus potential. The experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations, including couplings to the low-lying 2⁺ and 3⁻ states in the target and projectile. The calculated results show that the universal functions of the Guo 2013 and Prox. 77 models provide the lowest and highest fusion barriers, respectively. In addition, it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy ones. The highest sensitivity to the mass number of the projectile belongs to the results of Prox. 77. A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping configurations. Our results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 model. For the heavier systems, the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

We study the dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with nucleons, which takes place in high-energy proton-nucleus collisions. The quark interchange between a nucleon and a $c\bar{c}$ meson leads to the dissociation of the $c\bar{c}$ meson. We consider the reactions: ${pR}\to {{\rm{\Lambda }}}_{c}^{+}{\bar{D}}^{0}$, ${pR}\to {{\rm{\Lambda }}}_{c}^{+}{\bar{D}}^{* 0}$, ${pR}\to {{\rm{\Sigma }}}_{c}^{++}{D}^{-}$, ${pR}\to {{\rm{\Sigma }}}_{c}^{++}{D}^{* -}$, ${pR}\to {{\rm{\Sigma }}}_{c}^{+}{\bar{D}}^{0}$, ${pR}\to {{\rm{\Sigma }}}_{c}^{+}{\bar{D}}^{* 0}$, ${pR}\to {{\rm{\Sigma }}}_{c}^{* ++}{D}^{-}$, ${pR}\to {{\rm{\Sigma }}}_{c}^{* ++}{D}^{* -}$, ${pR}\to {{\rm{\Sigma }}}_{c}^{* +}{\bar{D}}^{0}$, and ${pR}\to {{\rm{\Sigma }}}_{c}^{* +}{\bar{D}}^{* 0}$, where R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a $c\bar{c}$ meson corresponds to a reaction of a proton and the $c\bar{c}$ meson by replacing the up quark with the down quark and vice versa. Transition-amplitude formulas are derived from the S-matrix element. Unpolarized cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. The cross sections relate to nodes in the radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.

The effective liquid drop model (ELDM) is improved by introducing an accurate nuclear charge radius formula and an analytic expression for assaulting frequency. Within the improved effective liquid drop model (IMELDM), the experimental cluster radioactivity half-lives of the trans-lead region are calculated. It is shown that the accuracy of the IMELDM is improved compared with that of the ELDM. At last, the cluster radioactivity half-lives that are experimentally unavailable for the trans-lead nuclei are predicted by the IMELDM. These predictions may be useful for searching for new candidates for cluster radioactivity in future experiments.

Based on the potential-energy-surface calculation, the impact of different deformation degrees of freedom on a single-particle structure and binding energies in nuclei around ¹⁵²Nd, located on one of the hexadecapole-deformation islands, is analyzed in a multi-dimensional deformation space. Various energy maps, curves and tables are presented to indicate nuclear properties. The calculated equilibrium deformations and binding energies with different potential parameters are compared with experimental data and other theories. It is found that the inclusion of the hexadecapole deformations, especially the axial one, can improve the theoretical description of both nuclear shapes and masses. In addition, our calculated potential-energy curve shows that a critical deformation-point, β₂ ≈ 0.4, exists—the triaxial (hexadecapole) deformation effect can be neglectable but the hexadecapole (triaxial) one plays an important role before (after) such a critical point.

The nuclear modification factor for prompt photon production in proton-nucleus collisions is investigated within color dipole formalism. By means of the Glauber-Gribov approach, the nuclear effects are studied in various rapidity bins with the evolution equation-based saturation models and the phenomenological dipole models. The theoretical results are compared with the experimental data provided by PHENIX, ATLAS and CMS Collaborations. At forward rapidity and midrapidity, a reasonable agreement with the experimental data is shown for the theoretical results with the modified Kharzeev, Levin and Nardi model, and the Kowalski and Teaney model. Then, we analyze the influence of the initial state energy loss effect on the nuclear modification factor and find that it is obvious only at backward rapidity together with small p_T. Finally, the theoretical results are also compared with those of JETPHOX Monte Carlo program and the predictive results for the LHCb at very forward rapidities are presented.

We study the energy loss of a quark moving in a strongly coupled quark gluon plasma under the influence of anisotropy. The heavy quark drag force, diffusion coefficient, and jet quenching parameter are calculated using the Einstein-Maxwell-dilaton model, where the anisotropic background is characterized by an arbitrary dynamical parameter A. Our findings indicate that as the anisotropic factor A increases, the drag force and jet quenching parameter both increase, while the diffusion coefficient decreases. Additionally, we observe that the energy loss becomes more significant when the quark moves perpendicular to the anisotropy direction in the transverse plane. The enhancement of the rescaled jet quenching parameters near critical temperature T_c, as well as drag forces for a fast-moving heavy quark is observed, which presents one of the typical features of quantum chromodynamics phase transition.

The strong attractive interaction of the φ meson and the proton has recently been reported by the ALICE Collaboration. The corresponding scattering length f₀ is given as ${\rm{Re}}({f}_{0})=0.85\pm 0.34({\rm{stat}})\pm 0.14({\rm{syst}})$ and ${\rm{Im}}({f}_{0})=0.16\pm 0.10({\rm{stat}})\pm 0.09({\rm{syst}})$ fm. The fact that the real part is significant in contrast to the imaginary part indicates a dominant role of elastic scattering, whereas the inelastic process is less important. In this work, such scattering processes are inspected based on a unitary coupled-channel approach inspired by the Bethe–Salpeter equation. The φp scattering length is calculated based on this approach, and it is found that the experimental value of the φp scattering length can be obtained only if the attractive interaction of the φ meson and the proton is taken into account. A significant outcome of such attractive interaction is a two-pole structure in the φp scattering amplitude. One of the poles, located at (1969 − i283) MeV might correspond to N(1895)1/2⁻ or N(1875)3/2⁻ as listed in the review of the Particle Data Group (PDG). The other one, located at 1949 − i3 MeV should be a φN bound state, which has no counterpart in the PDG data.

A triaxially deformed relativistic Hartree–Bogoliubov theory in the Woods–Saxon basis is developed with the aim of treating the triaxial deformation, pairing correlations and continuum in a unified way. In order to consider the triaxial deformation, the deformed potentials are expanded in terms of spherical harmonic functions in the coordinate space. In order to take the pairing correlations into account and treat the continuum properly, by using the Dirac Woods–Saxon basis, which has correct asymptotic behavior, the relativistic Hartree–Bogoliubov equation with triaxial deformation is solved. The formalism of triaxially deformed relativistic Hartree–Bogoliubov theory in Woods–Saxon basis is presented. Taking an axially deformed nucleus ²⁴Ne and a triaxially deformed nucleus ⁷⁶Ge as examples, the numerical checks are performed. A weakly bound nucleus ¹¹²Ge is taken as an example to carry out the necessary converge checks for the numerical parameters. In addition, the ground-state properties of even–even germanium isotopes are investigated. The evolutions of two-neutron separation energy, deformation, root-mean-square radii and density distribution with mass number are analyzed. The comparison between the calculations from the relativistic Hartree–Bogoliubov theory based on harmonic-oscillator basis and the triaxially deformed relativistic Hartree–Bogoliubov theory in Woods–Saxon basis is performed. It is found that the neutron drip line is extended from ¹¹⁴Ge to ¹¹⁸Ge in the triaxially deformed relativistic Hartree–Bogoliubov theory in Woods–Saxon basis.

Pronounced changes of nuclear charge radii provide a stringent benchmark on the theoretical models and play a vital role in recognizing various nuclear phenomena. In this work, the systematic evolutions of nuclear charge radii along even Z = 84-120 isotopic chains are first investigated by the recently developed new ansatz under the covariant density functional. The calculated results show that the shell closure effects of nuclear charge radii appear remarkably at the neutron numbers N = 126 and 184. Interestingly, the arch-like shapes of charge radii between these two strong neutron-closed shells are naturally observed. Across the N = 184 shell closure, the abrupt increase in charge radii is still evidently emerged. In addition, the rapid raise of nuclear charge radii from the neutron numbers N = 138 to N = 144 is disclosed clearly in superheavy regions due to the enhanced shape deformation.

We demonstrate an optical realization for the rotating BTZ black hole using the recent popular photon fluid model in an optical vortex but with a new proposed expression for the optical phase. We also give the numerical realization for the optical vortex to ensure that it can be generated experimentally. Different from the earlier suggestions for the analogue rotating black holes, our proposal includes an inner horizon in the analogue black hole structure. Such structure can keep for a long distance for the convenience of observing analogue Hawking or Penrose radiations.

The structure properties for even–even nuclei around ²³⁰U, located on the hexadecapole-deformation island, are investigated using the potential-energy-surface calculation within the framework of the macroscopic−microscopic model. The impact of different deformation degrees of freedom (including axial and nonaxial quadrupole and hexadecapole deformations) on total energy, shell, and pairing contributions is analyzed, based on the projected energy maps and curves. The single-particle structure is presented and briefly discussed. To a large extent, a much better agreement with experimental data and other theoretical results is obtained if the hexadecapole deformations, especially the axial one, are taken into account. These results could provide useful insights into understanding the effects of different quadrupole and hexadecapole deformations.

Based on the liquid-drop model and using the first derivative of the normalized Gaussian function to consider the shell correction, a simple α-decay energy formula is proposed for heavy and superheavy nuclei. The values of corresponding adjustable parameters are obtained by fitting α-decay energies of 209 nuclei ranging from Z = 90 to Z = 118 with N ≥ 140. The calculated results are in good agreement with the experimental data. The average and standard deviations between the experimental data and theoretical results are 0.141 and 0.190 MeV, respectively. For comparison, the reliable formulae proposed by Dong T K et al (2010, Phys. Rev. C 82, 034 320), Dong J M et al (2010, Phys. Rev. C 81, 064 309) and the WS3+ nuclear mass model proposed by Wang N et al (2011, Phys. Rev. C 84, 051 303) are also used. The results indicate that our improved 7-parameter formula is superior to these empirical formulae and is largely consistent with the WS3+ nuclear mass model. In addition, we extend this formula to predict the α-decay energies for nuclei with Z = 117, 118, 119 and 120. The predicted results of these formulae are basically consistent.

Based on the systematic studies for low-lying states of the odd-A ⁴⁹⁻⁵⁷Mn isotopes, the ground-states inversion and the rotational properties of a ground-state-based sequence are revealed and discussed. The energy levels of low-lying states and electromagnetic moments in odd-A ⁴⁹⁻⁵⁷Mn isotopes have been well reproduced in shell-model calculations, and the above phenomena could be understood with obviously different occupation numbers in proton orbitals such as πf_7/2 and πp_3/2, which changes similarly with the obtained quadrupole deformation in covariant density functional theory (CDFT). After considering the coupling of collective rotation and intrinsic single-particle motion, the available experimental magnetic moments in ⁵³Mn and adjacent nuclei can be well explained with CDFT. The present calculations suggest that the 5/2⁻ and 7/2⁻ states in ⁵³Mn are formed by π5/2⁻[312] and π7/2⁻[303] respectively. Together with the behavior of levels, this provides proofs for the level sequences of low-lying states in ⁵³Mn distinct from the K^π = 5/2⁻ rotational band in ⁴⁹Cr and other odd-A Mn isotopes.