A shell-model nuclear level density

doi:10.1016/0375-9474(70)90862-6

Nuclear Physics A

Volume 159, Issue 2, December 1970, Pages 625-641

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Abstract

A nuclear level-density formula was derived by introducing a stepwise single-particle level structure. It was found to be formally identical to the well-known Fermi gas level density, when the level-density parameter a was regarded as a function of the excitation energy E instead of a constant. The computed level-density parameter was compared with that deduced from neutron resonance data.

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Calculation of double differential neutron cross-sections of 56Fe and 90Zr isotopes
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This study is concerned with the calculations of double differential neutron cross-sections of the structural fusion materials of ⁵⁶Fe and ⁹⁰Zr isotopes that are bombarded with protons. Calculations were performed using the level density models of the TALYS 1.95 code and PHITS 3.22 Monte Carlo code. Constant Temperature Fermi Gas, Back Shifted Fermi Gas, and Generalized Super Fluid Models were employed for level density models. Calculations were performed at 22.2 MeV proton energies. Calculations were compared with the experimental data taken from Experimental Nuclear Reaction Data (EXFOR). In conclusion, the results showed that the level density model results of TALYS 1.95 codes for the double differential neutron cross-sections of ⁵⁶Fe and ⁹⁰Zr isotopes are consistent with experimental data. On the other hand, PHITS 3.22 results gave lower cross-section values than experimental data at 120 and 150°.
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Citation Excerpt :
The other phenomenological level density model is the Back Shifted Fermi Gas Model (BSFGM) (Dilg et al., 1973). In addition to all of the above-mentioned models, the Generalised Superfluid Model is an important model that can produce considerable results (GSM) (Baba, 1970). The manner this model is characterized distinguishes it from the previously discussed models.
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Nuclear Physics A

Abstract

References (22)

Nucl. Phys.

Nucl. Phys.

Mat. Fys. Medd. Dan. Vid. Selsk.

Energia Nucleare

Japan Atomic Energy Research Institute Report

JAERI-1183

Can. J. Phys.

Can. J. Phys.

Phys. Rev.

Phys. Rev.

Nuovo Cim.

Phys. Rev.

Phys. Rev.

Adv. in Phys.

Cited by (124)

Analyzing neutron emission cross sections for 22.2 MeV proton-induced reactions on <sup>58</sup>Ni and <sup>52</sup>Cr

Calculation of double differential neutron cross-sections of <sup>56</sup>Fe and <sup>90</sup>Zr isotopes

Impact of the quenching of shell effects with excitation energy on nuclear level density

Investigation of the production routes of Palladium-103 and Iodine-125 radioisotopes

Effects of combining some theoretical models in the cross-section calculations of some alpha-induced reactions for <sup>nat</sup>Sb

Examination of the cross sections of the light-particle induced reactions for the <sup>99</sup>Tc transmutation