Modification of nuclear mass formula by considering isospin effects

Abstract

We propose a semiempirical nuclear mass formula based on the macroscopic-microscopic method in which the isospin and mass dependence of model parameters are investigated with the Skyrme energy density functional. The number of model parameters is considerably reduced compared with the finite range droplet model. The rms deviation with respect to 2149 measured nuclear masses is reduced by 21%, falling to 0.516 MeV. The new magic number N = 16 in light neutron-rich nuclei and the shape coexistence phenomena for some nuclei have been examined with the model. The shell corrections of superheavy nuclei are also predicted.

Toward global beyond-mean-field calculations of nuclear masses and low-energy spectra

“…Current theoretical nuclear mass tables are provided mainly by three different approaches: (a) microscopicmacroscopic (mic-mac) methods which improve the original liquid drop formula with microscopic corrections (the most commonly used of this kind are the finite-range droplet model (FRDM) [2,3] or, more recently, the Weizsäcker-Skyrme (WS) mass model [4,5]); (b) Duflo-Zuker (DZ) approach based a functional of occupation numbers guided by the interacting shell model method [6]; (c) microscopic methods based on Hartree-Fock-Bogoliubov (HFB) approaches with Skyrme (see Refs. [7,8] and references therein) and Gogny functionals [9].…”

β -decay properties of neutron-rich rare-earth isotopes

“…Transitions at N = 118 in Nd and at N = 120 in Ce are also predicted with Gogny-D1S. It is also worth comparing the above results with those from modern global mass models, such as the semiempirical nuclear mass formula based on macroscopic-microscopic methods [52]. This mass formula predicts a shape transition from prolate to oblate at N = 118, 122, 122, 120, 118, 118, 116 in Xe, Ba, Ce, Nd, Sm, Gd, and Dy, respectively.…”

Pairing interactions and one-nucleon separation energies

“…On the one hand, there are many theoretical efforts in describing and predicting the values of B, e.g., mean field approaches [1,2], macroscopicmicroscopic approaches [3,4], and liquid drop models [4,5]. On the other hand, the values of B exhibit various simplicities which provide us with a number of approaches to predict unknown binding energies by extrapolations.…”

“…These features were studied in terms of the symmetry energy of Ref. [4] and the pairing interaction of Ref. [16].…”