All Results

Odd systems in deformed relativistic Hartree Bogoliubov theory in continuum

LuluLi; JieMeng; P.Ring; En-GuangZhao; Shan-Gui ZhouSubjects: Physics >> Nuclear Physics

In order to describe the exotic nuclear structure in unstable odd-A or odd-odd nuclei, the de- formed relativistic Hartree Bogoliubov theory in continuum has been extended to incorporate the blocking effect due to the odd nucleon. For a microscopic and self-consistent description of pairing correlations, continuum, deformation, blocking effects, and the extended spatial density distribution in exotic nuclei, the deformed relativistic Hartree Bogoliubov equations are solved in a Woods-Saxon basis in which the radial wave functions have a proper asymptotic behavior at large r. The for- malism and numerical details are provided. The code is checked by comparing the results with those of spherical relativistic continuum Hartree Bogoliubov theory in the nucleus 19O. The prolate deformed nucleus 15C is studied by examining the neutron levels and density distributions. |

Halos in a deformed Relativistic Hartree-Bogoliubov theory in continuum

Lulu Li; Jie Mengh; P. RingEn-Guang ZhaoShan-Gui ZhouSubjects: Physics >> Nuclear Physics

In this contribution we present some recent results about neutron halos in deformed nuclei. A deformed relativistic Hartree-Bogoliubov theory in continuum has been developed and the halo phenomenon in deformed weakly bound nuclei is investigated. These weakly bound quantum systems present interesting examples for the study of the interdependence between the deformation of the core and the particles in the halo. Magnesium and neon isotopes are studied and detailed results are presented for the deformed neutron-rich and weakly bound nuclei 42Mg. The core of this nucleus is prolate, but the halo has a slightly oblate shape. This indicates a decoupling of the halo orbitals from the deformation of the core. The generic conditions for the existence of halos in deformed nuclei and for the occurrence of this decoupling effect are discussed. |

Zhen-HuaZhang; JieMeng; En-GuangZhao; Shan-GuiZhou

Subjects: Physics >> Nuclear Physics

The ground state band was recently observed in the superheavy nucleus 256Rf. We study the rotational properties of 256Rf and its neighboring even-even nuclei by using a cranked shell model (CSM) with the pairing correlations treated by a particle-number conserving (PNC) method in which the blocking effects are taken into account exactly. The kinematic and dynamic moments of inertia of the ground state bands in these nuclei are well reproduced by the theory. The spin of the lowest observed state in 256Rf is determined by comparing the experimental kinematic moments of inertia with the PNC-CSM calculations and agrees with previous spin assignment. The effects of the high order deformation ε6 on the angular momentum alignments and dynamic moments of inertia in these nuclei are discussed. |

submitted time
2017-07-30
Hits*1786*，
Downloads*1061*，
Comment
*0*

Microscopic and self-consistent description for neutron halo in deformed nuclei

Lulu Li; Jie Meng; P. Ring; En-Guang Zhao; Shan-Gui ZhouSubjects: Physics >> Nuclear Physics

AdeformedrelativisticHartree-Bogoliubovtheoryincontinuumhasbeendevelopedfor the study of neutron halos in deformed nuclei and the halo phenomenon in deformed weakly bound nuclei is investigated. Magnesium and neon isotopes are studied and some results are presented for the deformed neutron-rich and weakly bound nuclei 44Mg and 36Ne. The core of the former nucleus is prolate, but the halo has a slightly oblate shape. This indicates a decoupling of the halo orbitals from the deformation of the core. The generic conditions for the existence of halos in deformed nuclei and for the occurrence of this decoupling effect are discussed. |

Halos in medium-heavy and heavy nuclei with covariant density functional theory in continuum

J Meng; S G ZhouSubjects: Physics >> Nuclear Physics

The covariant density functional theory with a few number of parameters has been widely used to describe the ground-state and excited-state properties for the nuclei all over the nuclear chart. In order to describe exotic properties of unstable nuclei, the contribution of the continuum and its coupling with bound states should be treated properly. In this Topical Review, the development of the covariant density functional theory in continuum will be introduced, including the relativistic continuum Hartree-Bogoliubov theory, the relativistic Hartree-Fock-Bogoliubov theory in continuum, and the deformed relativistic Hartree-Bogoliubov theory in continuum. Then the descriptions and predictions of the neutron halo phenomena in both spherical and deformed nuclei will be reviewed. The diffuseness of the nuclear potentials, nuclear shapes and density distributions, and the impact of the pairing correlations on nuclear size will be discussed. |

submitted time
2017-07-30
Hits*1610*，
Downloads*1046*，
Comment
*0*

Sensitivity Study of Searching for $\tau^- \to \gamma \mu^-$ at HIEPA

Yu-Bo Li; Cheng-Ping Shen; Chang-Zheng YuanSubjects: Physics >> Nuclear Physics

The charged lepton flavor violation process is a clean and sensitive probe of new physics beyond the Standard Model. A sensitivity study is performed to the process?τ?→γμ??based on a 3~fb?1?inclusive Monte Carlo sample of?e+e??collisions at a center-of-mass energy of 4.26 or 4.6~GeV, in the framework of the BESIII software system. The 90\% confidence level upper limits on?$\BR(\tau^- \to \gamma \mu^-)$?are estimated assuming no signal is produced. We also obtain the sensitivity on?$\BR(\tau^- \to \gamma \mu^-)$?as a function of the integrated luminosity, to serve as a reference for the HIEPA being proposed in China. It is found that 6.34~ab?1?are needed to reach the current best upper limit of?4.4×10?8?and about 2510~ab?1?are needed to reach a sensitivity of?10?9?if the detector design is similar to that of BESIII. |

[1 Pages/ 6 Totals]