ParityProjected Shell Model Monte Carlo Level Densities for fpshell Nuclei
Abstract
We calculate paritydependent level densities for the eveneven isotopes 58,62,66Fe and 58Ni and the oddA nuclei 59Ni and 65Fe using the Shell Model Monte Carlo method. We perform these calculations in the complete fpgds shellmodel space using a pairing+quadrupole residual interaction. We find that, due to pairing of identical nucleons, the lowenergy spectrum is dominated by positive parity states. Although these pairs break at around the same excitation energy in all nuclei, the energy dependence of the ratio of negativetopositive parity level densities depends strongly on the particular nucleus of interest. We find equilibration of both parities at noticeably lower excitation energies for the oddA nuclei 59Ni and 65Fe than for the neighboring eveneven nuclei 58Ni and 66Fe.
 Authors:
 Gesellschaft fur Schwerionenforschung (GSI), Germany
 ORNL
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC)
 OSTI Identifier:
 932043
 DOE Contract Number:
 DEAC0500OR22725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review C; Journal Volume: 75; Journal Issue: 6
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ENERGY DEPENDENCE; EVENEVEN NUCLEI; EXCITATION; MONTE CARLO METHOD; NUCLEI; NUCLEONS; PARITY; RESIDUAL INTERACTIONS; SHELL MODELS; IRON ISOTOPES; NICKEL ISOTOPES
Citation Formats
Ozen, C., Langanke, K., MartinezPinedo, G., and Dean, David Jarvis. ParityProjected Shell Model Monte Carlo Level Densities for fpshell Nuclei. United States: N. p., 2007.
Web. doi:10.1103/PhysRevC.75.064307.
Ozen, C., Langanke, K., MartinezPinedo, G., & Dean, David Jarvis. ParityProjected Shell Model Monte Carlo Level Densities for fpshell Nuclei. United States. doi:10.1103/PhysRevC.75.064307.
Ozen, C., Langanke, K., MartinezPinedo, G., and Dean, David Jarvis. Mon .
"ParityProjected Shell Model Monte Carlo Level Densities for fpshell Nuclei". United States.
doi:10.1103/PhysRevC.75.064307.
@article{osti_932043,
title = {ParityProjected Shell Model Monte Carlo Level Densities for fpshell Nuclei},
author = {Ozen, C. and Langanke, K. and MartinezPinedo, G. and Dean, David Jarvis},
abstractNote = {We calculate paritydependent level densities for the eveneven isotopes 58,62,66Fe and 58Ni and the oddA nuclei 59Ni and 65Fe using the Shell Model Monte Carlo method. We perform these calculations in the complete fpgds shellmodel space using a pairing+quadrupole residual interaction. We find that, due to pairing of identical nucleons, the lowenergy spectrum is dominated by positive parity states. Although these pairs break at around the same excitation energy in all nuclei, the energy dependence of the ratio of negativetopositive parity level densities depends strongly on the particular nucleus of interest. We find equilibration of both parities at noticeably lower excitation energies for the oddA nuclei 59Ni and 65Fe than for the neighboring eveneven nuclei 58Ni and 66Fe.},
doi = {10.1103/PhysRevC.75.064307},
journal = {Physical Review C},
number = 6,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

We calculate paritydependent level densities for the eveneven isotopes {sup 58,62,66}Fe and {sup 58}Ni and the oddA nuclei {sup 59}Ni and {sup 65}Fe using the shell model Monte Carlo method. We perform these calculations in the complete fpgds shellmodel space using a pairing+quadrupole residual interaction. We find that, due to pairing of identical nucleons, the lowenergy spectrum is dominated by positive parity states. Although these pairs break at around the same excitation energy in all nuclei, the energy dependence of the ratio of negativetopositive parity level densities depends strongly on the particular nucleus of interest. We find equilibration of bothmore »

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