Stochastic analog neutron transport with TRIPOLI4 and FREYA: Bayesian uncertainty quantification for neutron multiplicity counting
Abstract
From nuclear safeguards to homeland security applications, the need for the better modeling of nuclear interactions has grown over the past decades. Current Monte Carlo radiation transport codes compute average quantities with great accuracy and performance; however, performance and averaging come at the price of limited interactionbyinteraction modeling. These codes often lack the capability of modeling interactions exactly: for a given collision, energy is not conserved, energies of emitted particles are uncorrelated, and multiplicities of prompt fission neutrons and photons are uncorrelated. Many modern applications require more exclusive quantities than averages, such as the fluctuations in certain observables (e.g., the neutron multiplicity) and correlations between neutrons and photons. In an effort to meet this need, the radiation transport Monte Carlo code TRIPOLI4® was modified to provide a specific mode that models nuclear interactions in a full analog way, replicating as much as possible the underlying physical process. Furthermore, the computational model FREYA (Fission Reaction Event Yield Algorithm) was coupled with TRIPOLI4 to model complete fission events. As a result, FREYA automatically includes fluctuations as well as correlations resulting from conservation of energy and momentum.
 Authors:

 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 DEN, DM2S, SERMA, LTSD, GifsurYvette Cedex (France)
 Publication Date:
 Research Org.:
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1305864
 Report Number(s):
 LLNLJRNL674376
Journal ID: ISSN 00295639
 Grant/Contract Number:
 AC5207NA27344
 Resource Type:
 Accepted Manuscript
 Journal Name:
 Nuclear Science and Engineering
 Additional Journal Information:
 Journal Volume: 183; Journal Issue: 2; Journal ID: ISSN 00295639
 Publisher:
 American Nuclear Society
 Country of Publication:
 United States
 Language:
 English
 Subject:
 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 98 NUCLEAR DISARMAMENT, SAFEGUARDS AND PHYSICAL PROTECTION; 11 NUCLEAR FUEL CYCLE AND RUEL MATERIALS
Citation Formats
Verbeke, J. M., and Petit, O.. Stochastic analog neutron transport with TRIPOLI4 and FREYA: Bayesian uncertainty quantification for neutron multiplicity counting. United States: N. p., 2016.
Web. doi:10.13182/NSE1582.
Verbeke, J. M., & Petit, O.. Stochastic analog neutron transport with TRIPOLI4 and FREYA: Bayesian uncertainty quantification for neutron multiplicity counting. United States. https://doi.org/10.13182/NSE1582
Verbeke, J. M., and Petit, O.. Wed .
"Stochastic analog neutron transport with TRIPOLI4 and FREYA: Bayesian uncertainty quantification for neutron multiplicity counting". United States. https://doi.org/10.13182/NSE1582. https://www.osti.gov/servlets/purl/1305864.
@article{osti_1305864,
title = {Stochastic analog neutron transport with TRIPOLI4 and FREYA: Bayesian uncertainty quantification for neutron multiplicity counting},
author = {Verbeke, J. M. and Petit, O.},
abstractNote = {From nuclear safeguards to homeland security applications, the need for the better modeling of nuclear interactions has grown over the past decades. Current Monte Carlo radiation transport codes compute average quantities with great accuracy and performance; however, performance and averaging come at the price of limited interactionbyinteraction modeling. These codes often lack the capability of modeling interactions exactly: for a given collision, energy is not conserved, energies of emitted particles are uncorrelated, and multiplicities of prompt fission neutrons and photons are uncorrelated. Many modern applications require more exclusive quantities than averages, such as the fluctuations in certain observables (e.g., the neutron multiplicity) and correlations between neutrons and photons. In an effort to meet this need, the radiation transport Monte Carlo code TRIPOLI4® was modified to provide a specific mode that models nuclear interactions in a full analog way, replicating as much as possible the underlying physical process. Furthermore, the computational model FREYA (Fission Reaction Event Yield Algorithm) was coupled with TRIPOLI4 to model complete fission events. As a result, FREYA automatically includes fluctuations as well as correlations resulting from conservation of energy and momentum.},
doi = {10.13182/NSE1582},
journal = {Nuclear Science and Engineering},
number = 2,
volume = 183,
place = {United States},
year = {2016},
month = {6}
}
Web of Science