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arXiv · 2306.11422

Bulk and neutron-proton asymmetry coefficients of the semi-empirical mass formula tuned to ground state mass excess of AME2020 and/or FRDM(2012)

Dalip Singh Verma·Vivek·Kushmakshi
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Abstract

Davidson et al. has extended Seeger's mass formula to non-zero excitation energies by introducing temperature-dependent coefficients in the liquid drop energy part of the semi-empirical mass formula, without considering the shell effects. The semi-empirical mass formula of Davidson et al. is applicable for the compound nucleus temperatures less than or equal to 4 MeV. The mass excess calculated using this mass formula including shell effects/corrections does not reproduce the ground state mass excesses of the new atomic mass evaluation data AME2020 and/or FRDM(2012) with its coefficients at zero temperature. So, the coefficients of the semi-empirical mass formula are needed to be tuned to reproduce the ground state mass excess of the nuclei in the recent atomic mass evaluation data AME2020 and/or FRDM(2012). The bulk and neutron-proton asymmetry coefficients of the semi-empirical mass formula of Davidson et al. with shell effects have been tuned to reproduce the mass excess data for all the nuclei of AME2020 (Z=1-118 and A=1-295) and the nuclei of FRDM(2012) (Z=8-136 and A=16-339, except 3456 nuclei which are also available in the AME2020 data) at zero temperature, i.e., the coefficients are tuned for 9420 nuclei known at present. The tuned bulk and neutron-proton asymmetry coefficients reproduce the mass excess of the new atomic mass evaluation data AME2020 and/or FRDM(2012) within a difference of less than 1 MeV and can be used for the applications/investigations in the areas of physics where high energies are experienced or nuclei involved are in excited states, e.g., fusion-evaporation and fusion-fission processes in heavy-ion reactions.

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Dalip Singh Verma, Vivek, Kushmakshi. 2023-06-20. Bulk and neutron-proton asymmetry coefficients of the semi-empirical mass formula tuned to ground state mass excess of AME2020 and/or FRDM(2012). https://doi.org/10.1016/j.adt.2023.101619

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