Level density inputs in nuclear reaction codes and the role of the spin cutoff parameter

Voinov, A. V.; Grimes, S. M.; Brune, C. R.; Burger, A.; Gorgen, A.; Guttormsen, M.; Larsen, A. C.; Massey, T. N.; Siem, S.

doi:10.1016/j.nds.2014.08.070

Title: Level density inputs in nuclear reaction codes and the role of the spin cutoff parameter

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Abstract

Here, the proton spectrum from the ⁵⁷Fe(α,p) reaction has been measured and analyzed with the Hauser-Feshbach model of nuclear reactions. Different input level density models have been tested. It was found that the best description is achieved with either Fermi-gas or constant temperature model functions obtained by fitting them to neutron resonance spacing and to discrete levels and using the spin cutoff parameter with much weaker excitation energy dependence than it is predicted by the Fermi-gas model.

Authors:

Voinov, A. V. ^[1]; Grimes, S. M. ^[1]; Brune, C. R. ^[1]; Burger, A. ^[2]; Gorgen, A. ^[2]; Guttormsen, M. ^[2]; Larsen, A. C. ^[2]; Massey, T. N. ^[1]; Siem, S. ^[2]

Ohio Univ., Athens, OH (United States)
Univ. of Oslo, Oslo (Norway)

Publication Date:: Wed Sep 03 00:00:00 EDT 2014

Research Org.:: Ohio Univ., Athens, OH (United States)

Sponsoring Org.:: USDOE

Contributing Org.:: Ohio Univ., Athens, OH (United States)

OSTI Identifier:: 1253953

Grant/Contract Number:: FG02-88ER40387

Resource Type:: Accepted Manuscript

Journal Name:: Nuclear Data Sheets

Additional Journal Information:: Journal Volume: 119; Journal Issue: C; Journal ID: ISSN 0090-3752

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; level densities; parameters

Citation Formats


                    Voinov, A. V., Grimes, S. M., Brune, C. R., Burger, A., Gorgen, A., Guttormsen, M., Larsen, A. C., Massey, T. N., and Siem, S. Level density inputs in nuclear reaction codes and the role of the spin cutoff parameter.  United States: N. p., 2014. 
Web.  doi:10.1016/j.nds.2014.08.070.

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                    Voinov, A. V., Grimes, S. M., Brune, C. R., Burger, A., Gorgen, A., Guttormsen, M., Larsen, A. C., Massey, T. N., & Siem, S. Level density inputs in nuclear reaction codes and the role of the spin cutoff parameter.  United States.  https://doi.org/10.1016/j.nds.2014.08.070

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                    Voinov, A. V., Grimes, S. M., Brune, C. R., Burger, A., Gorgen, A., Guttormsen, M., Larsen, A. C., Massey, T. N., and Siem, S. Wed .  
"Level density inputs in nuclear reaction codes and the role of the spin cutoff parameter".  United States.  https://doi.org/10.1016/j.nds.2014.08.070.  https://www.osti.gov/servlets/purl/1253953.

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@article{osti_1253953,

  title        = {Level density inputs in nuclear reaction codes and the role of the spin cutoff parameter},

  author       = {Voinov, A. V. and Grimes, S. M. and Brune, C. R. and Burger, A. and Gorgen, A. and Guttormsen, M. and Larsen, A. C. and Massey, T. N. and Siem, S.},

  abstractNote = {Here, the proton spectrum from the 57Fe(α,p) reaction has been measured and analyzed with the Hauser-Feshbach model of nuclear reactions. Different input level density models have been tested. It was found that the best description is achieved with either Fermi-gas or constant temperature model functions obtained by fitting them to neutron resonance spacing and to discrete levels and using the spin cutoff parameter with much weaker excitation energy dependence than it is predicted by the Fermi-gas model.},

  doi          = {10.1016/j.nds.2014.08.070},

  journal      = {Nuclear Data Sheets},

  number       = C,

  volume       = 119,

  place        = {United States},

  year         = {Wed Sep 03 00:00:00 EDT 2014},

  month        = {Wed Sep 03 00:00:00 EDT 2014}

}

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