分类: 物理学 >> 核物理学 提交时间: 2017-08-22
摘要: The ground state properties including radii, density distribution and one neutron separation energy for C, N, O and F isotopes up to the neutron drip line are systematically studied by the fully self-consistent microscopic Relativistic Continuum Hartree-Bogoliubov (RCHB) theory. With the proton density distribution thus obtained, the charge-changing cross sections for C, N, O and F isotopes are calculated using the Glauber model. Good agreement with the data has been achieved. The charge changing cross sections change only slightly with the neutron number except for proton-rich nuclei. Similar trends of variations of proton radii and of charge changing cross sections for each isotope chain is observed which implies that the proton density plays important role in determining the charge-changing cross sections.
分类: 物理学 >> 核物理学 提交时间: 2017-08-22
摘要: Based on the systematic investigation of the data available for A ≥ 40, a Z1/3 dependence for the nuclear charge radii is shown to be superior to the generally accepted A1/3 law. A delicate scattering of data around Rc/Z1/3 is infered as owing to the isospin effect and a linear dependence of Rc/Z1/3 on N/Z ( or (N − Z)/2 ) is found. This inference is well supported by the microscopic Relativistic Continuum Hartree-Bogoliubov (RCHB) calculation conducted for the proton magic Ca, Ni, Zr, Sn and Pb isotopes including the exotic nuclei close to the neutron drip line. With the linear isospin dependence provided by the data and RCHB theory, a new isospin dependent Z1/3 formula for the nuclear charge radii is proposed.
分类: 物理学 >> 核物理学 提交时间: 2017-08-22
摘要: 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 con- tinuum Hartree-Bogoliubov (RCHB) theory. Particulary, we study in detail the properties of even-even Ca isotopes due to the appearance of giant ha- los in neutron rich Ca nuclei near the neutron drip line. The RCHB theory is able to reproduce the experimental binding energies Eb and two neutron separation energies S2n very well. The predicted neutron drip line nuclei are 28O, 72Ca, 98Ni, 136Zr, 176Sn, and 266Pb, respectively. Halo and giant halo properties predicted in Ca isotopes with A > 60 are investigated in detail from the analysis of two neutron separation energies, nucleon density distri- butions, single particle energy levels, the occupation probabilities of energy levels including continuum states. The spin-orbit splitting and the diffuseness of nuclear potential in these Ca isotopes are studied also. Furthermore, we study the neighboring lighter isotopes in the drip line Ca region and find some possibility of giant halo nuclei in the Ne-Na-Mg drip line nuclei.
分类: 物理学 >> 核物理学 提交时间: 2017-08-22
摘要: The critical point nuclei in Sm isotopes, which marks the first order phase transition between spherical U(5) and axially deformed shapes SU(3), have been investigated in the microscopic quadrupole constrained relativistic mean field (RMF) model plus BCS method with all the most used interactions, i.e., NL1, NL3, NLSH and TM1. The calculated potential energy surfaces show a clear shape transition for the even-even Sm isotopes with N = 82 ∼ 96 and the critical point nuclei are found to be 148Sm, 150Sm and 152Sm. Similar conclusions can also be drawn from the microscopic neutron and proton single particle spectra.