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There are many studies in Odd–Even staggering (OES) of nuclear masses, but the research on nuclear masses by using the systematicness of OES is indeed very few. In this work, we analyze the relationship among the four neighboring nuclei based on the OES of nuclide chain with the same number of neutrons in atomic mass evaluation database (AME2016 database). Our purpose in this paper is to describe an empirical formula with one constant for OES of nuclear masses that can be useful in describing and predicting nuclear masses with mass number A ≥ 1 0 0. With the empirical formula and AME2016 database, the root-mean-square deviation (RMSD) of the nuclei that we have successfully obtained 172 keV for A ≥ 1 0 0 (the RMSD is 140 keV for A ≥ 1 5 8). This paper also uses Levenberg–Marquart (L-M) neural network approach to study the OES of nuclear masses (A ≥ 1 0 0 , RMSD ≃ 1 4 3 keV; A ≥ 1 5 8 , RMSD ≃ 1 1 9 keV). The results show that the RMSD of nuclear masses for A ≥ 1 0 0 based on neural network approach 30 keV decreases than that based on empirical formula (the accuracy is increased by about 17%). In addition, the predicted values based on the empirical formula and L-M neural network approach are consistent with the values in AME2020 database, and the difference between our predicted values based on AME2016 database and experimental values measured in recent years is small. These results show that the new relation for nuclear masses has good simplicity, accuracy and reliability. Accurate nuclear mass is helpful to the research of nuclear physics, nuclear technology and astrophysics. [ABSTRACT FROM AUTHOR]

In this paper, we get the nuclear mass-density parameter of known mass and known charge radius by using the AME2020 nuclear mass database and the CR2013 nuclear charge radius database. For the nuclei with N ≥ 2 1 , we obtained an empirical formula of the constant parameter equal to 0 for the difference of nuclear mass-density parameter between two neighboring isotope. That is, the nuclear mass-density parameter of the two neighboring isotopes was equal. By using this empirical formula combined with AME2020 and CR2013 databases, the calculated value of 625 nuclear charge radii was obtained. The root-mean-square deviation (RMSD) of nuclear charge radius that we have successfully obtained is σ = 0. 0 1 1 fm. In addition, one of the corrections is the neutron factor. This correction is the key improvement which reduces the RMSD to 0.0077 fm. Considering the neutron shell effect, the different shell ranges were divided into two categories for correction, and the RMSD was reduced to 0.0056 fm. Based on the revised empirical formula combined with the AME2020 database, the calculated and predicted values of nuclear charge radius were obtained with high accuracy. Some of these predictions are also very consistent with experimental values measured in recent years. In addition, we use BP neural network to study the difference of nuclear mass-density parameter on the basis of two categories. The RMSDs obtained are 0.0028 fm and 0.0038 fm, respectively. It can be seen that such a division has a certain degree of reliability and feasibility. These results show that the new relation proposed in this paper has simplicity and reliability, which can be compared with other local nuclear charge radius relations. [ABSTRACT FROM AUTHOR]

We have systematically studied the level density parameter, nuclear level density and decay width of neutron and fission of superheavy nuclei. This paper is validated by comparing with available experiments for 2 3 6 U and 2 4 0 Pu. The angular dependence of level density parameter, level densities and ratio of Γ n and Γ f the thermal excitation energy (U) have been studied in the superheavy region 1 0 4 ≤ Z ≤ 1 1 8. The role of entrance channel parameter on decay width of neutron and fission has been studied both in cold and hot fusion reactions in the superheavy region 1 0 4 ≤ Z ≤ 1 1 8. Systematic variation of Γ n and Γ f is observed in both the cases. Finally, predicted Γ n / Γ tot for the synthesis of superheavy nuclei Z = 1 1 9 and 120. [ABSTRACT FROM AUTHOR]

Neutron detection using gadolinium (Gd) and its prompt gamma-rays is vital because of the high cross-section of Gd on thermal neutrons, thereby leading to significant interest in neutron detection with Gd-converted or Gd-loaded detector. However, simultaneous detection of neutron and gamma-rays with a Gd-loaded scintillator has been given less attention. In this study, we explored the feasibility of the GdI3:Ce detector for simultaneous detection with Monte Carlo N-Particle transport extended simulation. Furthermore, we examined the physical properties of Gd for application in the radiation field mixed with neutron and gamma-rays. Similarly, we simulated the geometry of the GdI3:Ce scintillator and its spectra obtained under various conditions. The results showed that GdI3:Ce with a thickness of 1 cm is enough to absorb 90 % of photons with energy under 81 keV. A shorter source-to-detector distance and larger detector size were superior to detecting prompt gamma-rays emitted from neutron capture, not only the gamma-rays from isomeric transition (named as general gamma-ray in this paper). Ultimately, spectra taken with the Gd3:Ce scintillator under the radiation field mixed with neutrons and gamma-ray showed gamma-ray peaks from both radio-isotopes and Gd (n γ) Gd reaction, indicating the feasibility of the application of simultaneous detection. [ABSTRACT FROM AUTHOR]

In this paper, various ground state properties are explored for full isotonic(isotopic) chain of neutron number N (proton number Z) = 4 0 using different families of Relativistic Mean-Field theory. Several properties, such as nucleon separation energies, pairing energies, deformation, radii and nucleon density distributions, are evaluated and compared with the experimental data as well as those from other microscopic and macroscopic models. N = 4 0 isotonic chain presents ample of support for the neutron magicity and articulates double magicity in recently discovered 6 0 Ca and 6 8 Ni. Our results are in close conformity with the recently measured value of charge radius of 6 8 Ni [S. Kaufmann et al., Phys. Rev. Lett.124 (2020) 132502] which supports the N = 4 0 magicity. Contrarily, Zr isotopes (Z = 4 0) display variety of shapes leading to the phenomenon of shape transitions and shape co-existence. The role of 3s 1 / 2 state, which leads to central depletion if unoccupied, is also investigated. 1 6 5 6 S and 4 0 1 2 2 Zr are found to be doubly bubble nuclei. [ABSTRACT FROM AUTHOR]

In this paper, we have examined the nuclear structural properties of 190–210Au isotopes within the framework of the Hartree–Fock–Bogoliubov Model. For the theoretical calculations, we have used the UNEDF2 and SKP interactions. The studies include the shape evolution, quadrupole deformation parameter β 2 , nuclear electric quadrupole moment Q(b), single-particle energy levels, the binding energy per nucleon, nuclear charge radius, neutron rms radius, proton rms radius and neutron skin thickness. To analyze the accuracy of our theoretical results, we have presented the comparative analysis with experimental data and finite-range droplet model calculations. The adequate resemblance with experimental data is supporting our studies. We observe the oblate-prolate shape coexistence for 190Au, 193Au and 195Au using the UNEDF2 interaction. [ABSTRACT FROM AUTHOR]

In this paper, a number of characteristics of the new fundamental interaction are described. The interaction is carried by a massless pseudoscalar boson and extends to at least the electron neutrino, proton and neutron. A substantiation of the existence of such an interaction is supported by an good agreement between the theoretical and experimental rates of all the five observed processes with solar neutrinos. A bright manifestation of the new interaction is expected in the observation that its contribution to the rate of splitting of a number of light stable nuclei by reactor antineutrinos is approximately six orders of magnitude greater than the contribution of electroweak interaction. [ABSTRACT FROM AUTHOR]

The partial photonuclear σ (γ , n) + σ (γ , pn) and σ (γ , 2 n) and the total photonuclear cross-sections (the giant dipole resonance (GDR)) have been investigated theoretically for neodymium isotopes, namely 1 4 2 – 1 4 5 , 1 4 8 , 1 5 0 Nd, using framework of the EMPIRE 3.2.2 code. The energy, width and cross-section parameters of the GDR used in our calculations have been investigated in this paper depending on the deformation parameters of nuclei. The calculated results have been compared with the experimental data and with those calculated using Lorentzian fitting parameters. Our calculations show a good agreement for all isotopes under study and give better results than the results calculated with Lorentzian parameters. Furthermore, the neutron number dependence of the total and partial photonuclear cross-sections has also been discussed. The results appear that the EMPIRE code used is a perfect tool for reproducing the splitting in the GDR for deformed 1 5 0 Nd isotope in two distinct dipole modes which are perfectly consistent with the experimental results. It has also been shown that the present parameters are suitable parameters for reproducing the GDR for spherical, or nearly spherical, and the deformed ( 1 5 0 Nd) neodymium isotopes. The parameters have been indicating the small deformation in 1 4 8 Nd, which cannot be shown by the Lorentzian fitting parameters. [ABSTRACT FROM AUTHOR]

Studies on the cross-sections of (n,n α) reactions which are energetically possible, about 14 MeV neutrons are quite scarce. In this paper, the cross-sections of (n,n α) nuclear reactions at E n = 14–15 MeV are analyzed by using a new empirical formula based on the statistical theory. We show that neutron cross-sections are closely related to the Q -value of nuclear reaction, in particular for (n,n α) channels. Results obtained with this empirical formula show good agreement with the available measured cross-section values. We hope that the estimations on the cross-sections using the present formalism may be helpful in future studies in this field. [ABSTRACT FROM AUTHOR]

In this paper, the new experimental data on interactions of neutrons with carbon nuclei at 4.2 GeV/ c are presented. The comparative analysis of the average multiplicities and kinematical characteristics of the protons and charged pions in n 1 2 C and p 1 2 C collisions at 4.2 GeV/ c is made. [ABSTRACT FROM AUTHOR]

The paper discusses the results of measurement for three components of tensor analyzing power for the reaction of incoherent π 0 -meson photoproduction on a deuteron within the proton energy range of 15–200 MeV and the neutron energy range of 15–150 MeV. The experiment was performed on the deuterium internal gas target of VEPP-3 electron accelerator using the protons and neutrons coincidence counting technique. The results of measurements of the tensor analyzing power's components are compared with the results of statistical modeling performed within the frameworks of a theoretical model. [ABSTRACT FROM AUTHOR]

This paper studies the formation cross-sections of super heavy (SH) nuclei in some cold fusion reactions of radioactive neutron-rich projectiles with double-magic 208Pb target. In this study, the cross-sections of capture, fusion and evaporation residues in one- and two-neutron (1n and 2n) channels are calculated by using neutron-rich Fe, Ni and Zn projectiles are compared to the cross-sections calculated using stable Fe, Ni and Zn projectiles. The heights of fusion barrier and their positions in all reactions considered in this study are also compared to the heights and positions calculated using the estimation method proposed by Dutt and Puri. For cold fusion reactions with stable Fe, Ni and Zn projectiles, the heights of fusion barrier and the cross-sections of evaporation residues in 1n and 2n channels are compared to their corresponding experimental data. In general, for reactions using projectiles with the same proton number, the neutron-rich projectile is found to yield relatively-heavier mass of SH nucleus and larger evaporation residue cross-section, compared to those of the corresponding stable projectiles. However, in certain reactions, the cross-sections of neutron-rich projectile can be slightly larger or slightly smaller than that of the corresponding stable projectile. This behavior is highly affected by the charge of projectile and the fission barrier of the formed compound nucleus (CN). In addition, the 292114 is found to be the heaviest compound nucleus formed in cold fusion reaction by using neutron-rich nuclei as the projectile, but the cross-section of evaporation residue in one-neutron channel is still around few pico barns (pb). [ABSTRACT FROM AUTHOR]

In this paper, we discuss the charge and magnetization densities for proton and neutron in the transverse plane, whereas there are links between the generalized parton distributions (GPDs) and elastic form factors by means of sum rules. We use the extended Regge parameterization for large momentum transfer region for calculating Dirac and Pauli form factors which have been described in the electromagnetic form factors data, so we want to calculate the charge and magnetization densities for proton and neutron in the transverse plane and we also calculate and quark charge and magnetization densities. The extracted results are compared with other previous parameterizations. [ABSTRACT FROM AUTHOR]

Relativistic energy density functionals have become a standard framework for nuclear structure studies of ground state properties and collective excitations over the entire nuclide chart. In this paper, we review recent developments in modeling nuclear weak-interaction processes: Charge-exchange excitations and the role of isoscalar proton-neutron pairing, charged-current neutrino-nucleus reactions relevant for supernova evolution and neutrino detectors and calculation of β-decay rates for r-process nucleosynthesis. [ABSTRACT FROM AUTHOR]

In this paper, four-dimensional stochastic approach is applied on dynamics of fission process to calculate mean fission time and prescission neutron multiplicity. Elongation, neck thickness, mass asymmetry and orientation degree of freedom (K-coordinate) are four dimensions in dynamical calculations. In order to investigate the influence of the dissipation coefficient of K-coordinate, the stochastic dynamics of the orientation degree of freedom using nonconstant dissipation coefficient was studied. Calculations were done for the 16O+208Pb and 16O+232Th reactions. Obtained results were compared with a constant dissipation coefficient (γK = 0.077(MeVzs)-1/2). The mean fission time and prescission neutron multiplicity for nonconstant dissipation case were lower than for the constant one. [ABSTRACT FROM AUTHOR]

In this paper, we study the binding energies, radii, single-particle energies, spin-orbit potential and density profile for multi-strange hypernuclei in the range of light mass to superheavy mass region within the relativistic mean field (RMF) theory. The stability of multi-strange hypernuclei as a function of introduced hyperons (Λ and Σ) is investigated. The neutron, lambda and sigma mean potentials are presented for light to superheavy hypernuclei. The inclusion of hyperons affects the nucleon, lambda and sigma spin-orbit potentials significantly. The bubble structure of nuclei and corresponding hypernuclei is studied. Nucleon and lambda halo structures are also investigated. A large class of bound multi-strange systems formed from the combination of nucleons and hyperons (n, p, Λ, Σ+ and n, p, Λ, Σ-) is suggested in the region of superheavy hypernuclei which might be stable against the strong decay. These multi-strange systems might be produced in heavy-ion reactions. [ABSTRACT FROM AUTHOR]

In this paper, we use the lowest order constrained variational method to study the behavior of nuclear symmetry energy versus density and spin states of neutrons and protons with AV18 potential. The dependency of incompressibility at saturation density on isospin asymmetry, ferromagnetic spin states and antiferromagnetic spin states is also investigated. [ABSTRACT FROM AUTHOR]

The reaction 1 1 Li(p , t)9Li(gs) at an incident energy of 4.3 MeV is interpreted in terms of a simplistic distorted-wave Born approximation, which assumes simultaneous transfer of the halo neutrons. The halo neutrons involved in the reaction is treated as either a di-neutron cluster or individual entities. Either of these approaches appears to be a good approximation of the reaction mechanism, as would be expected from earlier studies. The dominant contribution to the yield of the reaction comes from the known (2 s 1 / 2 )2 neutron structure component of the ground state of 1 1 Li. Furthermore, the cross-section angular distribution seems to be relatively insensitive to the fact that 1 1 Li has an anomalously large radius due to its Borromean halo properties. Significantly this simple treatment of the reaction is in much better agreement with the experimental angular distribution than previous sophisticated calculations. The relevance and limitations of a more advanced theoretical treatment which includes coupled channel and sequential transfer are discussed in the context of the present results. [ABSTRACT FROM AUTHOR]

This paper discusses the parity of charged pions. It is shown that the original determination of the parity of the negatively charged pion using the capture of negatively charged pions in deuterium to form two neutrons is not conclusive if the pion has a complex substructure. It is demonstrated that this experiment is compatible with the mixed-parity nature of the π- arising in a recent composite model. A major consequence of this is that CP may be conserved in the $K^{0}-\bar{K^{0}}$ system. [ABSTRACT FROM AUTHOR]

In this paper, a formalism consisting of multi-dimensional Langevin equation (LE) and Scission point Transition State Model (SCTSM) have been applied to study the angle dependence of fragment's average spin for 16O + 209Bi and 16O + 232Th systems. The influence of asymmetry and deformation parameters, neck thickness of compound nucleus and pre-scission neutron multiplicity on the fragment's average spin is discussed. Results obtained using this approach are in better agreement with the experimental data as compared with the SCTSM. [ABSTRACT FROM AUTHOR]

In the framework of a recently developed alpha-cluster model a nucleus is represented as a core (alpha-cluster liquid drop with dissolved excess neutron pairs in it) and a nuclear molecule on its surface. From analysis of experimental nuclear binding energies one can find the number of alpha-clusters in the molecule and calculate the nuclear charge radii. It was shown that for isotopes of one Z with growing A the number of alpha-clusters in the molecule decreases to three, which corresponds to the nucleus 12C for even Z and 15N for odd Z, and the specific density of the core binding energy ρ grows and reaches its saturation value. In this paper it is shown that the value ρ=2.55 MeV/fm3 explains the particular number of excess neutrons in stable nuclei. [ABSTRACT FROM AUTHOR]

We study systematically the average property of fragmentation reaction and momentum dissipation induced by halo-nuclei in intermediate energy heavy ion collisions for different colliding systems and different beam energies within the isospin dependent quantum molecular dynamics model (IQMD). This study is based on the extended halo-nucleus density distributions, which indicates the average property of loosely inner halo nucleus structure, because the interaction potential and in-medium nucleon-nucleon cross section in IQMD model depend on the density distribution. In order to study the average properties of fragmentation reaction and momentum dissipation induced by halo-nuclei we also compare the results for the halo-nuclear colliding systems with those for corresponding stable colliding systems with same mass under the same incident channel condition. We find that the effect of extended halo density distribution on the fragment multiplicity and nuclear stopping (momentum dissipation) are important for the different beam energies and different colliding systems. For example the extended halo density distributions increase the fragment multiplicity but decrease the nuclear stopping for all of incident channel conditions in this paper. [ABSTRACT FROM AUTHOR]

We show that the projection evolution approach can reproduce the exponential decay law. The method can be potentially used to calculate the lifetimes of decaying nuclei. [ABSTRACT FROM AUTHOR]

The halo factor is one of the experimental data which describes a distribution of neutrons in the nuclear periphery. In the presented paper we use Skyrme-Hartree (SH) and the Relativistic Mean Field (RMF) models to calculate the neutron excess factor Δ[sub B] which differs slightly from the halo factor f[sub exp]. The results of the calculations are compared to the measured data. [ABSTRACT FROM AUTHOR]

The anomaly of the residual proton–neutron interaction δ V pn for Ra isotopes around N = 1 3 5 deviating from the general trend, the so-called Ra puzzle, is investigated within the framework of covariant density functional theory in three-dimensional lattice space. The potential energy surfaces in (β 2 0 , β 3 0) plane for Ra isotopes are given by the constrained calculations. The average values of proton–neutron interaction δ V pn extracted from the binding energies of Ra and Rn isotopes with axial, triaxial and reflection asymmetric calculations are compared with the data from AME2020 atomic mass evaluation. It is found that the octupole deformation provides a reasonable interpretation of the Ra puzzle. [ABSTRACT FROM AUTHOR]

This review presents the nuclei with octupole correlations in the A ≈ 8 0 mass region. The status of experimental data on the behavior of the energy displacement, the E 1 transition probability and intrinsic electric dipole moment have been reviewed. The evolutions of the octupole strength with the numbers of protons and neutrons are discussed. [ABSTRACT FROM AUTHOR]

In this work, a new approach is presented for determining the equation of state for pure neutron matter. This is valid in the temperature- and density-regime where the system behaves like a nonideal gas. Further, the calculations involved are confined to the nonrelativistic and low-energy (≤ 150 MeV) regime. The approach is based on evaluating the quantum second virial coefficient B q of the system, where the input potential is the Reid-93 soft-core potential for J ≤ 2 , together with the one-pion-exchange potential (OPEP) for higher J. The many-body phase shifts are determined within the framework of a generalized scattering theory, taken here as the Galitskii–Migdal–Feynman formalism. The integral equations involved are solved using a highly-accurate matrix-inversion method. These medium phase shifts are then inserted in the Beth–Uhlenbeck formula to determine B q . Once this coefficient has been calculated, other thermophysical properties of the system can be readily computed according to standard expressions. Specifically, these properties include the equation of state (pressure–temperature–density relations), Helmholtz (free) energy, entropy, mean internal energy, specific heat capacity and chemical potential. Our results are compared, whenever possible, to those of previous calculations. The agreement is, on the whole, fair considering that the available calculations vary considerably among themselves. [ABSTRACT FROM AUTHOR]

Based on the similarity renormalization group (SRG) method, proton and neutron asymmetry in the nuclear pseudospin is investigated for the deformed system. We have checked influences of every term on the proton pseudospin splitting and their correlation with nuclear deformation. Further, we have found that dynamical term always made a similar effect on the proton pseudospin symmetry (PSS), which is different from the neutron case. By exerting its influence on the dynamical term, the vector–isovector V ρ potential gives the main contribution to the isospin asymmetry in the PSS except for several deeply bound states. The phenomenon that isospin asymmetry in the PSS becomes worse for the levels closer to the continuum and its reasons is disclosed. [ABSTRACT FROM AUTHOR]

The nuclear structure and thermal quantities of the superheavy nucleus of 2 9 2 1 2 0 1 7 2 are studied in a recent developed framework of the Finite-Temperature Hartree–Fock–Bogoliubov (FT-HFB) by using a zero-range pairing and including the continuum effects. Analyzing the shell structure of this nucleus at both zero and finite temperature shows a dependence on the various Skyrme-type forces used and a shell closure occurrence at Z = 120 for protons and N = 172 for neutrons with a large gap energy where the pseudo-spin-orbit effects play a primordial role in the shell sequence at finite temperature which confirm the double magicity of 2 9 2 1 2 0 1 7 2 . Thermodynamic quantities are also studied in the same framework where the results are qualitatively similar to what are obtained in case of the hot ordinary nuclei. [ABSTRACT FROM AUTHOR]

The low-lying energy levels, B(E2) transition probabilities and g-factors of even–even medium-mass tellurium isotopes have been studied by employing the projected shell model (PSM) approach. The oblate ground state deformations are taken in this study that were predicted in previous relativistic Hartree Bogoliubov mean field study. The low-lying yrast and yrare states are reproduced well in these calculations. The energy and configuration of yre states are also predicted. The experimental B(E2) values and their systematics with neutron number are reproduced well in the medium-mass Te isotopes. The experimental data are available for g -factors of 2 + states of 1 2 0 , 1 2 2 Te isotopes which is in line with these calculations. The enhancement of g-factors at spin I = 6 + in all the Te isotopes considered may be attributable to the alignment of protons in (π g 7 / 2) 2 subshell. Furthermore, the reduction of g-factors at spin I = 1 0 + in 1 1 4 − 1 1 8 Te and I = 8 + in 1 2 0 , 1 2 2 Te may be attributable to the alignment of neutrons in the (ν h 1 1 / 2) 2 subshell. The 8 + states of 1 1 4 − 1 1 8 Te are envisaged to be of (π g 7 / 2) 2 nature and in 1 2 0 , 1 2 2 Te these states are found to be of (ν h 1 1 / 2) 2 nature. [ABSTRACT FROM AUTHOR]

The new experimental data on characteristics of the secondary particles associated with the leading protons in inelastic interactions of projectile neutrons and protons with target carbon nuclei at incident momentum 4.2 GeV/c (corresponds to incident kinetic energy 3.37 GeV) have been presented. The dependencies of the average multiplicities of the charged pions and accompanying protons on longitudinal as well as transverse momenta of the leading protons in n 1 2 C and p 1 2 C collisions at 4.2 GeV/c have been investigated. The experimental dependencies have been compared systematically with the Monte Carlo calculations using the modified FRITIOF model. On the whole, the kinematical characteristics of the leading protons in n 1 2 C and p 1 2 C collisions have proved to be practically the same, even though they are formed as a result of different processes. From a systematic comparison of the experimental data with the model calculations, we could conclude that for a realistic description of the studied experimental dependencies it is probably necessary to take into account the interaction of strings for the case when fragmentation of strings occurs not outside of the nucleus (as it is assumed in the model), but inside and, possibly, on the boundary of the nucleus in the modified FRITIOF model. [ABSTRACT FROM AUTHOR]

New empirical formulae for calculating the (n , p) reaction cross-sections were obtained by using the EXFOR experimental data for the neutron energy 14–15 MeV. Considering the average binding energy per nucleon and dependences of cross-section in the principal formula, we get empirical formulae for estimating the (n , p) reaction cross-sections for 122 nuclei in the mass number range of 1 8 ≤ A ≤ 2 0 5. The EMPIRE 3.2 and TALYS 1.95 codes have been used to evaluate the (n , p) cross-sections for the selected nuclei within the specified neutron energy. The comparison of calculated cross-sections from the present proposed formulae with those from codes and previous systematics reveals more accurate predictions of the experimental data. [ABSTRACT FROM AUTHOR]

The systematic search of axial ground state and the emergence of new gaps in neutron-rich 4 4 − 5 2 Ar isotopes are the challenging of current calculations of relativistic and nonrelativistic mean field models. For this purpose, we have employed the model based on Relativistic Hartree–Bogoliubov (RHB) with the density-dependent effective interaction of point coupling DD-PCX type. However, the nonrelativistic mean field calculations based on Hartree-Fock model were carried out with Skyrme SV-min parametrization. All the present calculations were performed within axial symmetries. The results provide that most of isotopes show an oblate-deformed ground state. In particular, 5 0 Ar and 5 2 Ar display a spherical shape in their ground states with SV-Min calculations. There is a notable signature of the sub-shell closure at neutron number N = 3 2 , whereas N = 3 4 is expected to be nearly quenched in the spherical ground. Furthermore, coexistence features are predicted in the neutron-rich 4 4 Ar isotope. We have also studied the neutron axial densities and its central depletion in the well-deformed grounds for the first time. In addition to these, the proton single-particle evolution and bubble-like structure at 4 6 Ar are very well reproduced with DD-PCX calculations. [ABSTRACT FROM AUTHOR]

The ν 1 h 1 1 / 2 band in 100Pd is investigated by the cranking covariant density functional theory (CDFT) with the particle-number-conservation shell-model-like approach (SLAP) to treat the pairing correlations. The experimental B (E 2) , moments of inertia, and the total angular momentum are well reproduced by our calculation. The deformations for neutrons, protons, and the whole nucleus behave in a similar way with the decreasing of β and the tiny change of γ with increasing rotational frequency ℏ ω from 0.2 to 0.6 MeV. The features of the antimagnetic rotation (AMR) are identified by above calculation results. To conclude, the configuration of AMR for 1 0 0 Pd given by the cranking CDFT-SLAP is π (1 g 9 / 2 ) − 4 ⊗ ν [ 1 h 1 1 / 2 (1 g 7 / 2) 3 ]. Furthermore, the configuration of π (1 g 9 / 2 ) − 4 ⊗ ν [ 1 h 1 1 / 2 (1 g 7 / 2) 2 2 d 5 / 2 ] , which presents the experimental result of low spins, is also presented. [ABSTRACT FROM AUTHOR]

The interaction strength between chiral doublet bands is studied using the two-band mixing picture and the particle rotor model (PRM). The present calculations indicate that the interaction strength between chiral doublet bands is equal to zero for the ideal case of the configuration with γ = 30°, and the interaction strength becomes larger as γ deviates from 30°. For γ = 15° or 45°, the average interaction strength is approximately 180 keV in the chiral region. [ABSTRACT FROM AUTHOR]

The effect of the density of the surface nucleons on the calculation of the total potential in reactions where the participant nuclei are on the stability line and at least one of the participant nuclei is rich in neutrons has been studied. The results obtained by the analysis of the 16O+209Bi, 16O+144Nd, and 16O+144Sm reactions using the Hartree–Fock calculations of the neutron and the proton densities show a decrease of about 0.67, 0.53, and 0.45 MeV of the fusion barrier height in comparison to the corresponding values obtained when the nuclear density is taken to be proportional to the nuclear charge. It is shown that this decrease is due to the variation of the ratio of the density of neutrons to that of the protons in outer regions of the nuclear densities of 209Bi, 144Nd, and 144Sm nuclei. [ABSTRACT FROM AUTHOR]

The properties of neutron matter are investigated in the framework of the extended Brueckner–Hartree–Fock approximation at zero temperature. Self-consistent calculations using different realistic interactions are reported for pure neutron matter. In this contribution, all the self-energies are calculated self-consistently. Using the self-energy, k-mass is evaluated using realistic NN interactions. Furthermore, the effect of hole–hole contributions is examined. We found that the hole–hole ladder brought about a non-negligible contribution. [ABSTRACT FROM AUTHOR]

The localization of fermions in extra dimensions, proposed by Arkani-Hamed and Schmaltz, is discussed as the source of the phenomenon of particle mixing. We work out the example of neutrinos in detail. [ABSTRACT FROM AUTHOR]

We have performed a systematic study for the nuclear structure of superheavy nuclei with a special emphasis on the nuclei with possible central depletion of proton and neutron density in the mass region A ∼ 3 0 0 using the Relativistic Hartree–Bogoliubov (RHB) framework. It has been observed that in the case of neutron density distribution, the occurrence of central depletion is related to the occupancy of 4s orbital and it is found to decrease with increasing occupancy of the 4s orbital. On the other hand, in the case of proton density distribution, the central density depletion is mainly due to the lowering of weakly bound p-orbital states close to the continuum as it is energetically favored to lower the Coulomb repulsion in the case of superheavy nuclei. Also, occupation probability of the lower angular momentum states (p-orbitals) lying near the Fermi level is strongly suppressed due to the weak centrifugal barrier and strong Coulomb repulsion in comparison to large angular momentum states (contributing to surface region mainly), resulting in central density depletion. Among the considered cases in the present work, the maximum depletion is observed for 2 9 2 1 2 0 and for 2 9 4 Og under spherically symmetric and axially deformed cases, respectively. [ABSTRACT FROM AUTHOR]

The existence of a new interaction involving the electron neutrino and the nucleons, which has received a convincing confirmation through a good agreement between the theoretical and experimental results concerning all observable processes with solar neutrinos, should also inevitably manifest itself in the deuteron disintegration by the neutral currents of reactor antineutrinos. The special attention is drawn to the problem of finding the neutron registration efficiency, discussed in the preparation of the experiment at the Sudbury Neutrino Observatory and in a number of special studies. Lessons are noted that can be learned from three long-standing experiments on the deuteron disintegration by reactor neutrinos. [ABSTRACT FROM AUTHOR]

The scale-dependence of the nucleon–nucleon (NN) potential, which in recent years has been extensively analyzed within the context of chiral effective field theory, is, in fact, inherent in any models constrained by a fit to scattering data. A comparison between a purely phenomenological potential and a set of local interactions derived from chiral effective field theory suggests that — owing to the ability to describe NN scattering at higher energies, as well as the deuteron momentum distribution obtained from the y -scaling analysis of electro-disintegration data — purely phenomenological potentials are best suited to describe nuclear dynamics at the scale relevant to neutron star matter and correlation effects in nuclei. The breakdown of the paradigm based on the description of nuclear systems in terms of point-like protons and neutrons is briefly discussed. [ABSTRACT FROM AUTHOR]

In nuclear theory, there is always a quest for possible extensions of the nuclear landscape and extending our knowledge to the limits of nuclear existence. In this study, we examine the stability and structural properties of a wide range of nuclei in super- and ultra-heavy region in a phenomenological semi-microscopic approach. we calculated the shell correlation energy, residual pairing correction energy, two-nucleon separation energy and two-nucleon energy gap for 3670 even–even nuclei along β -stability line and two-neutron driplines in the ranges 7 0 ≤ Z ≤ 2 7 4 with 8 0 ≤ N ≤ 5 4 8 and 7 0 ≤ Z ≤ 2 1 2 with 1 2 6 ≤ N ≤ 5 4 8 , respectively. To assure reliability and confidence of the new results in the ultra-heavy region, we extended the search space to include heavy and super-heavy nuclei. We report 83 double magic nuclei and address the predominance of proton and neutron magic numbers. Our calculations reproduced known results on nuclear magicity and present strong evidences on islands of stability and magic numbers in super- and ultra-heavy regions. We also address shifts in nuclear magicity along the nuclear landscape close to the β -stability line and close to the neutron rich regions. [ABSTRACT FROM AUTHOR]

The location of the neutron drip line, currently known for only the lightest elements, remains a fundamental question in nuclear physics. Its description is a challenge for microscopic nuclear energy density functionals, as it must take into account in a realistic way not only the nuclear potential, but also pairing correlations, deformation effects and coupling to the continuum. The recently developed deformed relativistic Hartree–Bogoliubov theory in continuum (DRHBc) includes all three aforementioned effects in the description of nuclei throughout the nuclear chart. Here, the DRHBc with the successful density functional PC-PK1 is used to investigate whether and how deformation influences the prediction for the neutron drip-line location for even–even nuclei with 8 ≤ Z ≤ 2 0 , where many isotopes are predicted deformed. The results are compared with those based on the spherical relativistic continuum Hartree–Bogoliubov (RCHB) theory and discussed in terms of shape evolution and the variational principle. It is found that the Ne and Ar drip-line nuclei are different after the deformation effect is included. The direction of the change is not necessarily towards an extended drip line, but rather depends on the evolution of the degree of deformation towards the drip line. Deformation effects as well as pairing and continuum effects treated in a consistent way can affect critically the theoretical description of the neutron drip-line location. [ABSTRACT FROM AUTHOR]

Alpha decay (AD) and spontaneous fission (SF) half-lives of superheavy nuclei 2 9 6 − 3 5 0 1 2 4 have been studied within the density-dependent cluster model. The alpha-nucleus potentials were calculated using the double-folding model with the realistic M3Y nucleon–nucleon interaction. To calculate nuclear half-lives, several semi-empirical formulas were used in addition to the Wentzel–Kramers–Brillouin (WKB) approximation. The calculated AD half-lives agree well with the values computed by the analytical formulas of Royer, the semi-empirical formula of Poenaru et al. and the Viola–Seaborg systematic. To identify the mode of decay of these nuclei, the SF half-lives were calculated using the semi-empirical formula given by Xu et al. The results show that among the isotopes studied, isotopes 3 1 2 − 3 1 8 1 2 4 can be survived from the SF and have a half-life greater than 1 0 − 6 (s). The study predicts 4 α chains from isotopes 3 1 2 , 3 1 3 1 2 4 , 3 α chains from isotopes 3 1 4 , 3 1 5 , 3 1 6 1 2 4 , 2 α chains from isotopes 3 1 7 , 3 1 8 1 2 4 and an AD from 3 1 9 , 3 2 0 1 2 4. These isotopes have a half-life long enough to be synthesized in the laboratory. Also, in the decay chains of these isotopes, it is observed that the nuclei 2 8 4 , 2 8 7 1 1 0 , 2 8 8 1 1 2 , 2 9 2 1 1 4 , 2 9 7 − 3 0 2 1 1 6 have higher half-lives than their neighbors. The neutron numbers corresponding to these isotopes are N = 1 6 3 , 1 6 4 , 1 6 5 , 1 7 2 , 1 7 4 , 1 7 7 indicating the magical or semi-magical behavior of these numbers, which is in good agreement with the research results. [ABSTRACT FROM AUTHOR]

We studied the charge radius ( r c ), neutron radius ( r n ), and neutron skin-thickness (Δ r = r n − r p ) over a chain of isotopes from C to Zr with the stable region to the neutron drip line. Theoretical calculations are done with axially deformed self-consistent relativistic mean-field theory (RMF) and effective nonlinear NL3 and NL3* interactions. The theoretically estimated values are compared with available experimental data and a reasonable agreement is noted. We additionally assessed the two-neutron separation energy ( S 2 n ) to mark the drip line nuclei of the considered isotopic series. In the reference of S 2 n , neutron magicity is also discussed. The calculated neutron radii are compared with empirical estimation made by r = r 0 N 1 / 3 to examine the abnormal trend of the radius for neutron drip line nuclei. In view to guide the long tails, the density distribution for some skin candidates is analyzed. Finally, neutron skin thickness is observed for the whole considered isotopic series. [ABSTRACT FROM AUTHOR]

The α -decay half-lives, T α , for five heavy and nine superheavy even–even nuclei with 8 4 ≤ Z ≤ 9 2 and 1 1 6 ≤ Z ≤ 1 3 2 , respectively, have been calculated within the density-dependent cluster model. The α -nucleus potential was derived by employing the double-folding model with a realistic N N interaction whose exchange part has a finite-range. We considered several isotopes for each Z -value. The behavior of log T α against the neutron number variation for different isotopes of each element is investigated. We found a clear similarity in the behavior of log T α for the isotopes of a number of successive elements. The proton pair in the emitted α particle, for these elements, comes from the same proton energy level. Also, the behavior of log T α with the parent neutron number, for different isotopes of an element, was found to be governed by the existence of neutron magic number or neutron-level closure. The possibility to correlate the behavior of log T α for several isotopes of a specific element with the proton and neutron energy levels of this element is investigated. Moreover, the behavior of log T α when adding successive proton pairs to fill the energy level at different neutron numbers is studied. This work can be considered as a significant step forward to correlate the behavior of log T α with the energy levels. [ABSTRACT FROM AUTHOR]

In this work, we identify a unique and novel feature of central density depletion in both proton and neutron named as doubly bubble nuclei in 5 0 ≤ Z (N) ≤ 8 2 region. The major role of 2d-3s single-particle (s.p.) states in the existence of halo and bubble nuclei is probed. The occupancy in s.p. state 3s 1 / 2 leads to the extended neutron density distribution or halo while the unoccupancy results in the central density depletion. By employing the Relativistic Mean-Field (RMF) approach along with NL3* parameter, the separation energies, s.p. energies, pairing energies, proton and neutron density profiles along with deformations of even–even nuclei are investigated. Our results are concise with few other theories and available experimental data. Emergence on new shell closure and the magicity of conventional shell closures are explored systematically in this yet unknown region. [ABSTRACT FROM AUTHOR]

The spectroscopic factor (SF) of doubly-magic nuclei, neutron shell closed and neutron-rich nuclei has been determined through (d , p) reaction in the projectile energy range from 3 to 26 MeV. The theoretical angular differential cross-sections of (d , p) reactions in scattering center-of-mass angles from 0 ∘ to 6 0 ∘ have been calculated using FRESCO and NRV-DWUCK5 codes. By comparing the theoretical angular differential cross-sections with available experimental angular differential cross-sections, the values of SF have been determined. The exponential increase of SF as a function of neutron separation energy normalized by spin of the recoil nuclei has been shown for the first time for doubly-magic nuclei. The similar type of trend has also been observed for neutron-rich as well as neutron shell closed nuclei as a function of neutron separation energy normalized by asymmetric factor of recoil nucleus. More experimental data are required to verify the trend predicted by this investigation. [ABSTRACT FROM AUTHOR]

In this study, we have investigated the α -decay chains of even–even superheavy nuclei Z = 1 2 0 in the range of 2 9 0 ≤ A ≤ 3 0 4. The Hartree–Fock–Bogoliubov model is used to calculate the binding energy of these superheavy nuclei. We have included the so-called SkP skyrme function as an effective force and the quadruple deformations. The semi-empirical formulas are used in the reproducing α -decay and spontaneous fission half-lives of these superheavy nuclei. By studying the decay chains of the Z = 120 isotopes and comparing them with the half-lives of spontaneous fission, it is predicted that the elements 2 7 8 1 1 4 , 2 8 4 1 1 4 , 2 7 4 1 1 4 , 2 8 2 1 1 6 , 2 8 0 1 1 6 , 2 9 0 1 1 6 , 2 9 2 1 1 6 , 2 8 4 1 1 8 , 2 9 4 1 1 8 and 2 9 2 1 2 0 are more stable than the neighboring isotopes in their parent α -decay chain. The corresponding neutron and proton numbers represent magical behavior that is in agreement with the numbers predicted before. In this range, the predicted nuclei are found to have large enough half-lives to synthesize them in a laboratory. [ABSTRACT FROM AUTHOR]

We propose the use of neutron poisons in reactions induced by radioactive beams as a test of theoretical models aiming to relate neutron capture in nuclei with neutron surrogate reactions such as (d , p) reactions. We exploit the approximations necessary to obtain a direct relation between the two reactions: surrogate versus neutron capture. We also show how this is intimately related to the momentum distribution of the neutron within the deuteron. The models we use are based on the theory of inclusive breakup reactions commonly employed in the treatment of incomplete fusion and surrogate method. Such theories were developed in the 1980s by Ichimura, Austern and Vincent [Phys. Rev. C32 (1985) 431], Udagawa and Tamura [Phys. Rev. C24 (1981) 1348] and Hussein and McVoy [Nucl. Phys. A445 (1985) 124]. We use these theories to derive an expression for the proton yield in the reaction A (d , p) X. The capture reaction n + A → X is then extracted using reasonable approximations. By recalling an old method proposed by Serber [Phys. Rev.80 (1950) 1098; Proc. Roy. Soc. A208 (1951) 559] we explain how the momentum distribution of neutrons within the deuteron will depend on the short-range dependence of the nucleon–nucleon force. The relevance of our work to nucleosynthesis in the rapid neutron capture process is emphasized. [ABSTRACT FROM AUTHOR]