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Title: Impact of alternative transmission coeffcient parameterizations on Hauser-Feshbach theory

Abstract

Here, we investigate different formulations of the transmission coefficient T c, including the form implied by Moldauer’s “sum rule for resonance reactions” and the Moldauer-Simonius form. Within these different formulations, we compute the neutron transmission coefficients in the resolved and unresolved resonance regions, allowing a direct comparison with the transmission coefficients computed using an optical model potential. For nuclei for which there are no measured resonances, these approaches allow one to predict the average neutron resonance parameters directly from the optical model and level densities. Some of the approaches are valid in both the strong and weak coupling limits (i.e., any value of the average width and mean level spacing). Finally, both the Moldauer-Simonius and Moldauer’s Sum Rule forms approaches suggest that superradiance, that is, the quantum chaotic enhancement of certain channels, may be a common phenomena in nuclear collisions. Our results suggest why superradiance has been previously overlooked. We apply our approach to neutron reactions on the closed shell 90Zr nucleus and the mid-shell 197Au nucleus.

Authors:
 [1];  [1];  [1]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
OSTI Identifier:
1460713
Alternate Identifier(s):
OSTI ID: 1465612
Report Number(s):
BNL-207837-2018-JAAM
Journal ID: ISSN 2469-9985; TRN: US1901906
Grant/Contract Number:  
SC0012704; AC02-98CH10886
Resource Type:
Accepted Manuscript
Journal Name:
Physical Review C
Additional Journal Information:
Journal Volume: 98; Journal Issue: 2; Journal ID: ISSN 2469-9985
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Brown, David A., Nobre, G. P. A., and Herman, M. W. Impact of alternative transmission coeffcient parameterizations on Hauser-Feshbach theory. United States: N. p., 2018. Web. doi:10.1103/PhysRevC.98.024616.
Brown, David A., Nobre, G. P. A., & Herman, M. W. Impact of alternative transmission coeffcient parameterizations on Hauser-Feshbach theory. United States. doi:10.1103/PhysRevC.98.024616.
Brown, David A., Nobre, G. P. A., and Herman, M. W. Tue . "Impact of alternative transmission coeffcient parameterizations on Hauser-Feshbach theory". United States. doi:10.1103/PhysRevC.98.024616. https://www.osti.gov/servlets/purl/1460713.
@article{osti_1460713,
title = {Impact of alternative transmission coeffcient parameterizations on Hauser-Feshbach theory},
author = {Brown, David A. and Nobre, G. P. A. and Herman, M. W.},
abstractNote = {Here, we investigate different formulations of the transmission coefficient Tc, including the form implied by Moldauer’s “sum rule for resonance reactions” and the Moldauer-Simonius form. Within these different formulations, we compute the neutron transmission coefficients in the resolved and unresolved resonance regions, allowing a direct comparison with the transmission coefficients computed using an optical model potential. For nuclei for which there are no measured resonances, these approaches allow one to predict the average neutron resonance parameters directly from the optical model and level densities. Some of the approaches are valid in both the strong and weak coupling limits (i.e., any value of the average width and mean level spacing). Finally, both the Moldauer-Simonius and Moldauer’s Sum Rule forms approaches suggest that superradiance, that is, the quantum chaotic enhancement of certain channels, may be a common phenomena in nuclear collisions. Our results suggest why superradiance has been previously overlooked. We apply our approach to neutron reactions on the closed shell 90Zr nucleus and the mid-shell 197Au nucleus.},
doi = {10.1103/PhysRevC.98.024616},
journal = {Physical Review C},
number = 2,
volume = 98,
place = {United States},
year = {2018},
month = {8}
}

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