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Title: New model of binding energies of heavy nuclei with Z{>=}90

Abstract

A new form of the binding energy formula of heavy nuclei with Z{>=}90 is proposed where new terms beyond the standard Bethe and Weizsaecker formula are introduced by analytical expressions. This can be considered an interesting development of the Bethe and Weizsaecker mass formula for heavy nuclei with Z{>=}90. Two versions of the formulae are presented. The first version of the formula can reproduce the 117 known binding energies of nuclei with Z{>=}90 and N{>=}140 with an average deviation 0.118 MeV. This is the first time that the binding energies of heavy nuclei with Z{>=}90 and N{>=}140 can be calculated very accurately by a formula with only seven parameters. The binding energies, {alpha}-decay energies, and {alpha}-decay half-lives of unknown superheavy nuclei are predicted. The second version of the formula is obtained by fitting the 181 data of nuclei with Z{>=}90 with nine parameters and good agreement with experimental binding energies is also reached for all nuclei with Z{>=}90.

Authors:
 [1];  [1];  [2]
  1. Department of Physics, Nanjing University, Nanjing 210008 (China)
  2. (China)
Publication Date:
OSTI Identifier:
20771107
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 72; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevC.72.064331; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ACTINIDE NUCLEI; ALPHA DECAY; BINDING ENERGY; HALF-LIFE; MASS FORMULAE; MEV RANGE; TRANSACTINIDE ELEMENTS; WEIZSAECKER FORMULA

Citation Formats

Dong Tiekuang, Ren Zhongzhou, and Center of Theoretical Nuclear Physics, National Laboratory of Heavy-Ion Accelerator, Lanzhou 730000. New model of binding energies of heavy nuclei with Z{>=}90. United States: N. p., 2005. Web. doi:10.1103/PhysRevC.72.064331.
Dong Tiekuang, Ren Zhongzhou, & Center of Theoretical Nuclear Physics, National Laboratory of Heavy-Ion Accelerator, Lanzhou 730000. New model of binding energies of heavy nuclei with Z{>=}90. United States. doi:10.1103/PhysRevC.72.064331.
Dong Tiekuang, Ren Zhongzhou, and Center of Theoretical Nuclear Physics, National Laboratory of Heavy-Ion Accelerator, Lanzhou 730000. Thu . "New model of binding energies of heavy nuclei with Z{>=}90". United States. doi:10.1103/PhysRevC.72.064331.
@article{osti_20771107,
title = {New model of binding energies of heavy nuclei with Z{>=}90},
author = {Dong Tiekuang and Ren Zhongzhou and Center of Theoretical Nuclear Physics, National Laboratory of Heavy-Ion Accelerator, Lanzhou 730000},
abstractNote = {A new form of the binding energy formula of heavy nuclei with Z{>=}90 is proposed where new terms beyond the standard Bethe and Weizsaecker formula are introduced by analytical expressions. This can be considered an interesting development of the Bethe and Weizsaecker mass formula for heavy nuclei with Z{>=}90. Two versions of the formulae are presented. The first version of the formula can reproduce the 117 known binding energies of nuclei with Z{>=}90 and N{>=}140 with an average deviation 0.118 MeV. This is the first time that the binding energies of heavy nuclei with Z{>=}90 and N{>=}140 can be calculated very accurately by a formula with only seven parameters. The binding energies, {alpha}-decay energies, and {alpha}-decay half-lives of unknown superheavy nuclei are predicted. The second version of the formula is obtained by fitting the 181 data of nuclei with Z{>=}90 with nine parameters and good agreement with experimental binding energies is also reached for all nuclei with Z{>=}90.},
doi = {10.1103/PhysRevC.72.064331},
journal = {Physical Review. C, Nuclear Physics},
number = 6,
volume = 72,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
  • A local formula of binding energy for heavy and superheavy nuclei has very recently been proposed [Dong and Ren, Phys. Rev. C 72, 064331 (2005)]. In this paper, the limit of the predictive ability of this local formula is investigated. It is found that the neutron-proton correlations should be considered when higher precision is required. On the one hand, we introduce a new term |N-Z-50|/A, and on the other hand we consider the different strengths of proton-proton, neutron-neutron, and neutron-proton pairing correlations. For the first time, the standard deviation {radical}({sigma}{sup 2}) of the binding energies for 117 nuclei with Z{>=}90more » and N{>=}140 is reduced to 0.105 MeV. The {alpha} decay energies Q{sub {alpha}} and half-lives T{sub {alpha}} of nuclei with Z=102-118 are reproduced quite well. The proton drip line of superheavy elements from Md (Z=101) to Ds (Z=110) are predicted.« less
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