Sensitivity of Photoneutron Production to Perturbations in Cross-Section Data
نویسندگان
چکیده
The most recent release of photonuclear interaction data for Monte Carlo applications is the ENDF/B-VII library. While this current version offers several improvements over its predecessors, it does not address the observed, sometimes quite significant variance in the measured data. For instance, for U, the cross-section data in the ENDF/B-VII library is consistently larger than all measurements except for those by Caldwell, et al., occasionally by as much as 20%. The objective of the work performed here was to investigate the sensitivity of photoneutron production to perturbations in photonuclear cross-section data. The effect of these perturbations on experimental observables in a common setup was assessed using the MCNPX/MCNP-PoliMi code system. Since the standard MCNPX perturbation routines are not available for photonuclear reactions, a new methodology to evaluate the sensitivity of commonlymeasured parameters to perturbations in photonuclear cross-section data was developed and implemented. The results of the analysis show that the maximum variance applied to the cross section (20%) results in an integral detector response change that in general varies between 4% and 8% for the exact configuration considered here. However, the methodology is general and may be readily applied to any source-target configuration.
منابع مشابه
Monte Carlo study of photoneutron production in U-235 following perturbations in cross section data
Article history: Received 8 October 2008 Received in revised form 19 November 2008 Accepted 19 November 2008 Available online 12 January 2009 0306-4549/$ see front matter 2008 Elsevier Ltd. A doi:10.1016/j.anucene.2008.11.023 * Corresponding author. Tel.: +1 734 615 7830; fax E-mail address: [email protected] (S.D. Clarke). Active photon interrogation systems may be employed to detect high-Z i...
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