The relativistic Hartree-Bogoliubov(RHB)theory is a powerful tool for describing exotic nuclei near drip lines.The key technique is to solve the RHB equation in the coordinate space to obtain the quasi-particle states...The relativistic Hartree-Bogoliubov(RHB)theory is a powerful tool for describing exotic nuclei near drip lines.The key technique is to solve the RHB equation in the coordinate space to obtain the quasi-particle states.In this paper,we solve the RHB equation with the Woods-Saxon-type mean-field and Delta-type pairing-field potentials by using the finite-difference method(FDM).We inevitably obtain spurious states when using the common symmetric central difference formula(CDF)to construct the Hamiltonian matrix,which is similar to the problem resulting from solving the Dirac equation with the same method.This problem is solved by using the asymmetric difference formula(ADF).In addition,we show that a large enough box is necessary to describe the continuum quasi-particle states.The canonical states obtained by diagonalizing the density matrix constructed by the quasi-particle states are not particularly sensitive to the box size.Part of the asymptotic wave functions can be improved by applying the ADF in the FDM compared to the shooting method with the same box boundary condition.展开更多
We study the proton magic O, Ca, Ni, Zr, Sn, and Pb isotope chains from the proton drip line to the neutron drip line with the relativistic continuum Hartree-Bogoliubov (RCHB) theory. Particulary, we study in detail t...We study the proton magic O, Ca, Ni, Zr, Sn, and Pb isotope chains from the proton drip line to the neutron drip line with the relativistic continuum Hartree-Bogoliubov (RCHB) theory. Particulary, we study in detail the properties of even-even Ca isotopes due to the appearance of giant halos in neutron rich Ca nuclei near the neutron drip line. The RCHB theory is able to reproduce the experimental binding energiesE b and two neutron separation energiesS 2n very well. The predicted neutron drip line nuclei are28O,72Ca,98Ni,136Zr,176Sn, and266Pb. Halo and giant halo properties predicted in Ca isotopes withA>60 are investigated in detail through analysis of two neutron separation energies, nucleon density distributions, single particle energy levels, and the occupation probabilities of energy levels including continuum states. The spin-orbit splitting and the diffuseness of nuclear potential in these Ca isotopes, as well as the neighboring lighter isotopes in the drip line Ca region and find certain possibilities of giant halo nuclei in the Ne?Na?Mg drip line nuclei are also studied.展开更多
The radial basis function(RBF) approach is a powerful tool to improve nuclear mass predictions. By combining the RBF approach with the latest relativistic continuum Hartree-Bogoliubov(RCHB) model, the local systematic...The radial basis function(RBF) approach is a powerful tool to improve nuclear mass predictions. By combining the RBF approach with the latest relativistic continuum Hartree-Bogoliubov(RCHB) model, the local systematic deviations between the RCHB mass predictions and the experimental data are eliminated, and the root-meansquare(rms) mass deviation is significantly reduced from 7.923 MeV to 0.386 MeV. However, systematic deviations between the RBF improved mass predictions and the experimental data remain for nuclei with four different odd-even parities, i.e.(even Z, even N),(even Z, odd N),(odd Z, even N), and(odd Z, odd N). They can be reduced by separately training RBF for the four groups of nuclei, and the resulting rms deviation decreases to 0.229 MeV. It is found that the RBF approach can describe the deformation effects neglected in the present RCHB mass calculations, and also improves the description of the shell effect and the pairing effect.展开更多
The ground-state properties of N=3 isotones and mirror nuclei have been investigated in the Rrelativistic Continuum Hartree-Bogoliubov theory with the NLSH effective interaction. Pairing correlations are taken into ac...The ground-state properties of N=3 isotones and mirror nuclei have been investigated in the Rrelativistic Continuum Hartree-Bogoliubov theory with the NLSH effective interaction. Pairing correlations are taken into account by a density-dependent 5-force. The calculations show that the proton density distributions of SB and 9C have a long tail, the core has an increasing tendency of 9C and the paired off valence protons make the halo distribution shrink. The cross sections for the 8B(gC)+12C reaction which are consistent with the experimental data are calculated using the Glauber model. On the whole, we think that SB is a one-proton halo nucleus and 9C is a two-proton halo nucleus.展开更多
The inner fission barriers of the even-even uranium isotopes from the proton to the neutron drip line are examined using the deformed relativistic Hartree-Bogoliubov theory in continuum.A periodic-like evolution for t...The inner fission barriers of the even-even uranium isotopes from the proton to the neutron drip line are examined using the deformed relativistic Hartree-Bogoliubov theory in continuum.A periodic-like evolution for the ground state shapes is shown with respect to the neutron number,i.e.,spherical shapes at shell closures 126,184,258,and prolate dominated shapes between them.Analogous to the shape evolution,the inner fission barriers also exhibit a periodic-like behavior:peaks at the shell closures and valleys in the mid-shells.The triaxial effect on the inner fission barrier is evaluated using triaxial relativistic mean field calculations combined with a simple BCS method for pairing.When the triaxial correction is included,the inner barrier heights show good consistency with available empirical data.Additionally,the evolution from the proton to the neutron drip line aligns with results from the multi-dimensionally constrained relativistic mean field theory.A flat valley in the fission barrier height is predicted around the neutron-rich nucleus U which may play a role of fission recycling in astrophysical r-process nucleosynthesis.展开更多
The collective Bamiltonian up to the fourth order for multi-O(4) model is derived based on the self-consistent collective-coordinate (SCC) method, which is formulated in the framework of the time-dependent Hartree...The collective Bamiltonian up to the fourth order for multi-O(4) model is derived based on the self-consistent collective-coordinate (SCC) method, which is formulated in the framework of the time-dependent Hartree-Bogoliubov (TDHB) theory. The validity of the collective Hamiltonian is checked in the two special cases of the multi-O(4) model: the case where the number of the shells is equal to one (a single j-shell case), and the case where the Hartree-Bogoliubov equilibrium point is spherical (the spherical case). The collective Hamiltonian constitutes a good starting point to study nuclear shape coexistence.展开更多
Taking ^120Sn as an example, we discuss the pseudospin symmetry in the single proton resonant states by examining the energies, widths and the wavefunctions. The information of the single proton resonant states in sph...Taking ^120Sn as an example, we discuss the pseudospin symmetry in the single proton resonant states by examining the energies, widths and the wavefunctions. The information of the single proton resonant states in spherical nuclei are extracted from an analytic continuation in the coupling constant method within the framework of the self-consistent relativistic mean field theory under the relativistic boundary condition. We find small energy splitting in a pair of pseudospin partners in the resonant states. The lower components of the Dirac wavefunctions of a pseudospin doublet agree well in the region where nuclear potential dominates. It is concluded that the pseudospin symmetry is also well conserved for the resonant states in realistic nuclei.展开更多
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 co...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 nucleus24Ne and a triaxially deformed nucleus76Ge as examples,the numerical checks are performed.A weakly bound nucleus112Ge 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 from114Ge to118Ge in the triaxially deformed relativistic Hartree–Bogoliubov theory in Woods–Saxon basis.展开更多
Nuclear masses play a crucial role in both nuclear physics and astrophysics,driving sustained efforts toward precise experi-mental determination and reliable theoretical predictions.In this study,we compiled the newly...Nuclear masses play a crucial role in both nuclear physics and astrophysics,driving sustained efforts toward precise experi-mental determination and reliable theoretical predictions.In this study,we compiled the newly measured masses for 296 nuclides from 40 references published between 2021 and 2024,subsequent to the release of the latest atomic mass evalu-ation.These data were used to benchmark the performance of several relativistic and nonrelativistic density functionals,including PC-PK1,TMA,SLy4,SV-min,UNEDF1,and the recently proposed PC-L3R.The results for PC-PK1 and PC-L3R were obtained using the state-of-the-art deformed relativistic Hartree-Bogoliubov theory in continuum(DRHBc),whereas the others were adopted from the existing literature.It was found that the DRHBc calculations with PC-PK1 and PC-L3R achieved an accuracy better than 1.5 MeV,outperforming the other functionals,which all exhibited root-mean-square devia-tions exceeding 2 MeV.The odd-even effects and isospin dependence in these theoretical descriptions were examined.The PC-PK1 and PC-L3R descriptions were qualitatively similar,exhibiting robust isospin dependence along the isotopic chains.Finally,a quantitative comparison between the PC-PK1 and PC-L3R results is presented,with the largest discrepancies analyzed in terms of the potential energy curves from the constrained DRHBc calculations.展开更多
The collective Hamiltonian up to the fourth order for a multi-O(4) model is derived for the first time based on the self-consistent collective-coordinate(SCC) method,which is formulated in the framework of the time-de...The collective Hamiltonian up to the fourth order for a multi-O(4) model is derived for the first time based on the self-consistent collective-coordinate(SCC) method,which is formulated in the framework of the time-dependent Hartree-Bogoliubov(TDHB) theory.This collective Hamiltonian is valid for the spherical case where the HB equilibrium point of the multi-O(4) model is spherical as well as for the deformed case where the HB equilibrium points are deformed.Its validity is tested numerically in both the spherical and deformed cases.Numerical simulations indicate that the low-lying states of the collective Hamiltonian and the transition amplitudes among them mimic fairly well those obtained by exactly diagonalizing the Hamiltonian of the multi-O(4) model.The numerical results for the deformed case imply that the "optimized RPA boundary condition" is also valid for the well-known η*,η expansion around the unstable HB point of the multi-O(4) model.All these illuminate the power of the SCC method.展开更多
The kernel ridge regression(KRR)method and its extension with odd-even effects(KRRoe)are used to learn the nuclear mass table obtained by the relativistic continuum Hartree-Bogoliubov theory.With respect to the bindin...The kernel ridge regression(KRR)method and its extension with odd-even effects(KRRoe)are used to learn the nuclear mass table obtained by the relativistic continuum Hartree-Bogoliubov theory.With respect to the binding energies of 9035 nuclei,the KRR method achieves a root-mean-square deviation of 0.96 MeV,and the KRRoe method remarkably reduces the deviation to 0.17 MeV.By investigating the shell effects,one-nucleon and twonucleon separation energies,odd-even mass differences,and empirical proton-neutron interactions extracted from the learned binding energies,the ability of the machine learning tool to grasp the known physics is discussed.It is found that the shell effects,evolutions of nucleon separation energies,and empirical proton-neutron interactions are well reproduced by both the KRR and KRRoe methods,although the odd-even mass differences can only be reproduced by the KRRoe method.展开更多
The low-lying electric dipole strengths in proton-rich nuclei 17F and 17Ne, which can be produced at HIRFL-CSR in Lanzhou, are investigated. In the framework of the covariant density functional theory the self-consist...The low-lying electric dipole strengths in proton-rich nuclei 17F and 17Ne, which can be produced at HIRFL-CSR in Lanzhou, are investigated. In the framework of the covariant density functional theory the self-consistent relativistic Hartree Bogoliubov model and the relativistic quasiparticle random phase approximation with the NL3 parameter set and Gogny pairing interaction are adopted in the calculations. A pronounced dipole peak appears below 10 MeV in17Ne, but does not occur in 17F. The prop erties of this low-lying E1 excitation in 17Ne are studied, which may correspond to a proton pygmy resonance with different characteristics from those of giant dipole resonance.展开更多
基金Supported by the National Natural Science Foundation of China(11775119,2175109)the Natural Science Foundation of Tianjin,China(19JCYBJC30800)。
文摘The relativistic Hartree-Bogoliubov(RHB)theory is a powerful tool for describing exotic nuclei near drip lines.The key technique is to solve the RHB equation in the coordinate space to obtain the quasi-particle states.In this paper,we solve the RHB equation with the Woods-Saxon-type mean-field and Delta-type pairing-field potentials by using the finite-difference method(FDM).We inevitably obtain spurious states when using the common symmetric central difference formula(CDF)to construct the Hamiltonian matrix,which is similar to the problem resulting from solving the Dirac equation with the same method.This problem is solved by using the asymmetric difference formula(ADF).In addition,we show that a large enough box is necessary to describe the continuum quasi-particle states.The canonical states obtained by diagonalizing the density matrix constructed by the quasi-particle states are not particularly sensitive to the box size.Part of the asymptotic wave functions can be improved by applying the ADF in the FDM compared to the shooting method with the same box boundary condition.
基金the Major State Basic Research Development Program Under Contract Number G2000077407the National Natural Science Foundation of China (Grant Nos. 10025522, 10221003, 10047001, and 19935030)
文摘We study the proton magic O, Ca, Ni, Zr, Sn, and Pb isotope chains from the proton drip line to the neutron drip line with the relativistic continuum Hartree-Bogoliubov (RCHB) theory. Particulary, we study in detail the properties of even-even Ca isotopes due to the appearance of giant halos in neutron rich Ca nuclei near the neutron drip line. The RCHB theory is able to reproduce the experimental binding energiesE b and two neutron separation energiesS 2n very well. The predicted neutron drip line nuclei are28O,72Ca,98Ni,136Zr,176Sn, and266Pb. Halo and giant halo properties predicted in Ca isotopes withA>60 are investigated in detail through analysis of two neutron separation energies, nucleon density distributions, single particle energy levels, and the occupation probabilities of energy levels including continuum states. The spin-orbit splitting and the diffuseness of nuclear potential in these Ca isotopes, as well as the neighboring lighter isotopes in the drip line Ca region and find certain possibilities of giant halo nuclei in the Ne?Na?Mg drip line nuclei are also studied.
基金Supported by the National Natural Science Foundation of China(11805004,11875070 and 11711540016)the Natural Science Foundation of Anhui Province(1708085QA10)+2 种基金the Key Research Foundation of Education Ministry of Anhui Province(KJ2016A026 and SK2018A0577)the Doctor Foundation of Anhui Jianzhu University 2017(2017QD18)the Open fund for Discipline Construction,Institute of Physical Science and Information Technology,Anhui University
文摘The radial basis function(RBF) approach is a powerful tool to improve nuclear mass predictions. By combining the RBF approach with the latest relativistic continuum Hartree-Bogoliubov(RCHB) model, the local systematic deviations between the RCHB mass predictions and the experimental data are eliminated, and the root-meansquare(rms) mass deviation is significantly reduced from 7.923 MeV to 0.386 MeV. However, systematic deviations between the RBF improved mass predictions and the experimental data remain for nuclei with four different odd-even parities, i.e.(even Z, even N),(even Z, odd N),(odd Z, even N), and(odd Z, odd N). They can be reduced by separately training RBF for the four groups of nuclei, and the resulting rms deviation decreases to 0.229 MeV. It is found that the RBF approach can describe the deformation effects neglected in the present RCHB mass calculations, and also improves the description of the shell effect and the pairing effect.
基金Supported by Fundamental Research Funds for Cental Universities (XDJK2010D005,XDJK2010C049)National Natural Science Foundation of China (11075133,10205019)
文摘The ground-state properties of N=3 isotones and mirror nuclei have been investigated in the Rrelativistic Continuum Hartree-Bogoliubov theory with the NLSH effective interaction. Pairing correlations are taken into account by a density-dependent 5-force. The calculations show that the proton density distributions of SB and 9C have a long tail, the core has an increasing tendency of 9C and the paired off valence protons make the halo distribution shrink. The cross sections for the 8B(gC)+12C reaction which are consistent with the experimental data are calculated using the Glauber model. On the whole, we think that SB is a one-proton halo nucleus and 9C is a two-proton halo nucleus.
基金Supported by the Natural Science Foundation of Henan Province,China(242300421156,202300410480)the National Natural Science Foundation of China(12141501,U2032141,11935003)+1 种基金the State Key Laboratory of Nuclear Physics and Technology,Peking University(NPT2023ZX03)the Super Computing Center of Beijing Normal University,and High-performance Computing Platform of Peking University。
文摘The inner fission barriers of the even-even uranium isotopes from the proton to the neutron drip line are examined using the deformed relativistic Hartree-Bogoliubov theory in continuum.A periodic-like evolution for the ground state shapes is shown with respect to the neutron number,i.e.,spherical shapes at shell closures 126,184,258,and prolate dominated shapes between them.Analogous to the shape evolution,the inner fission barriers also exhibit a periodic-like behavior:peaks at the shell closures and valleys in the mid-shells.The triaxial effect on the inner fission barrier is evaluated using triaxial relativistic mean field calculations combined with a simple BCS method for pairing.When the triaxial correction is included,the inner barrier heights show good consistency with available empirical data.Additionally,the evolution from the proton to the neutron drip line aligns with results from the multi-dimensionally constrained relativistic mean field theory.A flat valley in the fission barrier height is predicted around the neutron-rich nucleus U which may play a role of fission recycling in astrophysical r-process nucleosynthesis.
基金The project supported by the Director Foundation from the Department of Nuclear Physics of China Institute of Atomic Energy under Grant Nos. 11SZZ200501 and 11SZZ200601 0ne of the authors (J.Z. Gu) is grateful to H. Aiba, K. Hagino, K. Matsuyanagi, S. Mizutori, F. Sakata, and Y.Z. Zhuo for valuable discussions on this subject. He also acknowledges support from Postdoctoral Fellowship for Foreign Researchers of the Japan Society for the Promotion of Science with thanks.
文摘The collective Bamiltonian up to the fourth order for multi-O(4) model is derived based on the self-consistent collective-coordinate (SCC) method, which is formulated in the framework of the time-dependent Hartree-Bogoliubov (TDHB) theory. The validity of the collective Hamiltonian is checked in the two special cases of the multi-O(4) model: the case where the number of the shells is equal to one (a single j-shell case), and the case where the Hartree-Bogoliubov equilibrium point is spherical (the spherical case). The collective Hamiltonian constitutes a good starting point to study nuclear shape coexistence.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10447102, 10475003, 10435010 and 10605004, and the Scientific Research Innovation Foundation of BUAA.
文摘Taking ^120Sn as an example, we discuss the pseudospin symmetry in the single proton resonant states by examining the energies, widths and the wavefunctions. The information of the single proton resonant states in spherical nuclei are extracted from an analytic continuation in the coupling constant method within the framework of the self-consistent relativistic mean field theory under the relativistic boundary condition. We find small energy splitting in a pair of pseudospin partners in the resonant states. The lower components of the Dirac wavefunctions of a pseudospin doublet agree well in the region where nuclear potential dominates. It is concluded that the pseudospin symmetry is also well conserved for the resonant states in realistic nuclei.
基金the Sichuan Normal University for financial support(No.341813001)。
文摘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 nucleus24Ne and a triaxially deformed nucleus76Ge as examples,the numerical checks are performed.A weakly bound nucleus112Ge 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 from114Ge to118Ge in the triaxially deformed relativistic Hartree–Bogoliubov theory in Woods–Saxon basis.
基金supported by the National Natural Science Foundation of China(Nos.12265012 and 12305125)Guizhou Provincial Science and Technology Projects(No.ZK[2022]203)+2 种基金PhD fund of Guizhou Minzu University(No.GZMUZK[2024]QD76)the National Key Laboratory of Neutron Science and Technology(No.NST202401016)the Sichuan Science and Technology Program(No.2024NSFSC1356).
文摘Nuclear masses play a crucial role in both nuclear physics and astrophysics,driving sustained efforts toward precise experi-mental determination and reliable theoretical predictions.In this study,we compiled the newly measured masses for 296 nuclides from 40 references published between 2021 and 2024,subsequent to the release of the latest atomic mass evalu-ation.These data were used to benchmark the performance of several relativistic and nonrelativistic density functionals,including PC-PK1,TMA,SLy4,SV-min,UNEDF1,and the recently proposed PC-L3R.The results for PC-PK1 and PC-L3R were obtained using the state-of-the-art deformed relativistic Hartree-Bogoliubov theory in continuum(DRHBc),whereas the others were adopted from the existing literature.It was found that the DRHBc calculations with PC-PK1 and PC-L3R achieved an accuracy better than 1.5 MeV,outperforming the other functionals,which all exhibited root-mean-square devia-tions exceeding 2 MeV.The odd-even effects and isospin dependence in these theoretical descriptions were examined.The PC-PK1 and PC-L3R descriptions were qualitatively similar,exhibiting robust isospin dependence along the isotopic chains.Finally,a quantitative comparison between the PC-PK1 and PC-L3R results is presented,with the largest discrepancies analyzed in terms of the potential energy curves from the constrained DRHBc calculations.
基金国家自然科学基金资助项目(1087515010775183+3 种基金10535010)国家重点基础研究发展规划(2007CB815000)德国Bundesministerium für Bildungund Forschung项目(06MT246)DFG优秀团队项目资助(www.universe-cluster.de)~~
基金Supported by the National Natural Science Foundation of China (Grant No.10675170)the Major State Basic Research Development Program of China (Grant No.2007CB815003)
文摘The collective Hamiltonian up to the fourth order for a multi-O(4) model is derived for the first time based on the self-consistent collective-coordinate(SCC) method,which is formulated in the framework of the time-dependent Hartree-Bogoliubov(TDHB) theory.This collective Hamiltonian is valid for the spherical case where the HB equilibrium point of the multi-O(4) model is spherical as well as for the deformed case where the HB equilibrium points are deformed.Its validity is tested numerically in both the spherical and deformed cases.Numerical simulations indicate that the low-lying states of the collective Hamiltonian and the transition amplitudes among them mimic fairly well those obtained by exactly diagonalizing the Hamiltonian of the multi-O(4) model.The numerical results for the deformed case imply that the "optimized RPA boundary condition" is also valid for the well-known η*,η expansion around the unstable HB point of the multi-O(4) model.All these illuminate the power of the SCC method.
基金Supported by the National Natural Science Foundation of China(11875075,11935003,11975031,12141501,12070131001)the China Postdoctoral Science Foundation under(2021M700256)+1 种基金the State Key Laboratory of Nuclear Physics and Technology,Peking University(NPT2023ZX01,NPT2023KFY02)the President’s Undergraduate Research Fellowship(PURF)of Peking University
文摘The kernel ridge regression(KRR)method and its extension with odd-even effects(KRRoe)are used to learn the nuclear mass table obtained by the relativistic continuum Hartree-Bogoliubov theory.With respect to the binding energies of 9035 nuclei,the KRR method achieves a root-mean-square deviation of 0.96 MeV,and the KRRoe method remarkably reduces the deviation to 0.17 MeV.By investigating the shell effects,one-nucleon and twonucleon separation energies,odd-even mass differences,and empirical proton-neutron interactions extracted from the learned binding energies,the ability of the machine learning tool to grasp the known physics is discussed.It is found that the shell effects,evolutions of nucleon separation energies,and empirical proton-neutron interactions are well reproduced by both the KRR and KRRoe methods,although the odd-even mass differences can only be reproduced by the KRRoe method.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10775183, 10875150 and 11075213)the National Basic Research Program of China (Grant No. 2007CB815000)
文摘The low-lying electric dipole strengths in proton-rich nuclei 17F and 17Ne, which can be produced at HIRFL-CSR in Lanzhou, are investigated. In the framework of the covariant density functional theory the self-consistent relativistic Hartree Bogoliubov model and the relativistic quasiparticle random phase approximation with the NL3 parameter set and Gogny pairing interaction are adopted in the calculations. A pronounced dipole peak appears below 10 MeV in17Ne, but does not occur in 17F. The prop erties of this low-lying E1 excitation in 17Ne are studied, which may correspond to a proton pygmy resonance with different characteristics from those of giant dipole resonance.