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Title: Nuclear Level densities from drip line to drip line

Abstract

New energy-, spin-, parity-dependent level densities based on the microscopic combinatorial model are presented and compared with available experimental data as well as with other nuclear level densities usually employed in nuclear reaction codes. These microscopic level densities are made available in a table format for nearly 8500 nuclei.

Authors:
 [1];  [2]
  1. CEA/DAM Ile de France, DPTA/Service de Physique Nucleaire, BP 12, 91680 Bruyeres-le-Chatel (France)
  2. Institut d'Astronomie et d'Astrophysique, Universite Libre de Bruxelles, Campus de la plaine CP 226, B-1050 Brussels (Belgium)
Publication Date:
OSTI Identifier:
21056760
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 891; Journal Issue: 1; Conference: 6. Symposium on nuclear physics, Tours (France), 5-8 Sep 2006; Other Information: DOI: 10.1063/1.2713536; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; COMPARATIVE EVALUATIONS; ENERGY LEVELS; ENERGY-LEVEL DENSITY; NUCLEAR MATTER; NUCLEAR MODELS; NUCLEAR REACTIONS; NUCLEAR STRUCTURE; NUCLEI; PARITY; SPIN

Citation Formats

Hilaire, S., and Goriely, S. Nuclear Level densities from drip line to drip line. United States: N. p., 2007. Web. doi:10.1063/1.2713536.
Hilaire, S., & Goriely, S. Nuclear Level densities from drip line to drip line. United States. doi:10.1063/1.2713536.
Hilaire, S., and Goriely, S. Mon . "Nuclear Level densities from drip line to drip line". United States. doi:10.1063/1.2713536.
@article{osti_21056760,
title = {Nuclear Level densities from drip line to drip line},
author = {Hilaire, S. and Goriely, S.},
abstractNote = {New energy-, spin-, parity-dependent level densities based on the microscopic combinatorial model are presented and compared with available experimental data as well as with other nuclear level densities usually employed in nuclear reaction codes. These microscopic level densities are made available in a table format for nearly 8500 nuclei.},
doi = {10.1063/1.2713536},
journal = {AIP Conference Proceedings},
number = 1,
volume = 891,
place = {United States},
year = {Mon Feb 26 00:00:00 EST 2007},
month = {Mon Feb 26 00:00:00 EST 2007}
}
  • New energy-, spin- and parity-dependent nuclear level densities based on the microscopic combinatorial model are proposed for practical applications. The combinatorial model includes a detailed microscopic calculation of the intrinsic state density and of the rotational enhancement factor, but a phenomenological treatment of the vibrational effect. The vibrational description has been improved using a boson partition function to construct phonons' state densities which are then folded in with the incoherent particle-hole densities. The present model is shown to predict the experimental s-wave neutron resonance spacings with a degree of accuracy comparable to that of the best global models available.
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  • Based on the {beta}-NMR method with spin-polarized radioactive-isotope beams, we have been conducting a series of experiments at RIKEN for the measurement the magnetic moments and electric quadrupole moments of light unstable nuclei. From the systematic measurements of nuclear moments in the unstable nuclear region, the effects of the neutron excess on the structure have been discussed. In the {mu}-moment measurements of the nitrogen isotopes, the outward-directed deviation of {mu}(17N) and {mu}(19N) from the Schmidt value were observed. In the case of Q-moment, our experimental data show large discrepancy from the shell-model predictions if neutron and proton effective charges aremore » assumed to be constant. By introducing an isospin dependence to the effective charges, the observed Q-moments of boron isotopes can be explained. We also applied the result of {mu}-moment measurements to the I{pi} assignment. Owing to the large difference of {mu} values among expected I{pi} candidates, I{pi}(17C)=3/2+ has been definitely assigned.« less