SecondOrder Sensitivity Analysis of Uncollided Particle Contributions to Radiation Detector Responses
This work presents an application of Cacuci’s SecondOrder Adjoint Sensitivity Analysis Methodology (2ndASAM) to the simplified Boltzmann equation that models the transport of uncollided particles through a medium to compute efficiently and exactly all of the first and secondorder derivatives (sensitivities) of a detector’s response with respect to the system’s isotopic number densities, microscopic cross sections, source emission rates, and detector response function. The offtheshelf PARTISN multigroup discrete ordinates code is employed to solve the equations underlying the 2ndASAM. The accuracy of the results produced using PARTISN is verified by using the results of three test configurations: (1) a homogeneous sphere, for which the response is the exactly known total uncollided leakage, (2) a multiregion twodimensional (rz) cylinder, and (3) a tworegion sphere for which the response is a reaction rate. For the homogeneous sphere, results for the total leakage as well as for the respective first and secondorder sensitivities are in excellent agreement with the exact benchmark values. For the nonanalytic problems, the results obtained by applying the 2ndASAM to compute sensitivities are in excellent agreement with centraldifference estimates. The efficiency of the 2ndASAM is underscored by the fact that, for the cylinder, only 12 adjoint PARTISN computations weremore »
 Authors:

^{[1]}
;
^{[2]}
 Univ. of South Carolina, Columbia, SC (United States)
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Publication Date:
 Report Number(s):
 LAUR1728959
Journal ID: ISSN 00295639
 Grant/Contract Number:
 AC5206NA25396
 Type:
 Accepted Manuscript
 Journal Name:
 Nuclear Science and Engineering
 Additional Journal Information:
 Journal Volume: 190; Journal Issue: 2; Journal ID: ISSN 00295639
 Publisher:
 American Nuclear Society  Taylor & Francis
 Research Org:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org:
 USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation (NA20)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; secondorder adjoint sensitivity analysis; particle and radiation transport; response variance and skewness
 OSTI Identifier:
 1441310
Cacuci, Dan G., and Favorite, Jeffrey A.. SecondOrder Sensitivity Analysis of Uncollided Particle Contributions to Radiation Detector Responses. United States: N. p.,
Web. doi:10.1080/00295639.2018.1426899.
Cacuci, Dan G., & Favorite, Jeffrey A.. SecondOrder Sensitivity Analysis of Uncollided Particle Contributions to Radiation Detector Responses. United States. doi:10.1080/00295639.2018.1426899.
Cacuci, Dan G., and Favorite, Jeffrey A.. 2018.
"SecondOrder Sensitivity Analysis of Uncollided Particle Contributions to Radiation Detector Responses". United States.
doi:10.1080/00295639.2018.1426899. https://www.osti.gov/servlets/purl/1441310.
@article{osti_1441310,
title = {SecondOrder Sensitivity Analysis of Uncollided Particle Contributions to Radiation Detector Responses},
author = {Cacuci, Dan G. and Favorite, Jeffrey A.},
abstractNote = {This work presents an application of Cacuci’s SecondOrder Adjoint Sensitivity Analysis Methodology (2ndASAM) to the simplified Boltzmann equation that models the transport of uncollided particles through a medium to compute efficiently and exactly all of the first and secondorder derivatives (sensitivities) of a detector’s response with respect to the system’s isotopic number densities, microscopic cross sections, source emission rates, and detector response function. The offtheshelf PARTISN multigroup discrete ordinates code is employed to solve the equations underlying the 2ndASAM. The accuracy of the results produced using PARTISN is verified by using the results of three test configurations: (1) a homogeneous sphere, for which the response is the exactly known total uncollided leakage, (2) a multiregion twodimensional (rz) cylinder, and (3) a tworegion sphere for which the response is a reaction rate. For the homogeneous sphere, results for the total leakage as well as for the respective first and secondorder sensitivities are in excellent agreement with the exact benchmark values. For the nonanalytic problems, the results obtained by applying the 2ndASAM to compute sensitivities are in excellent agreement with centraldifference estimates. The efficiency of the 2ndASAM is underscored by the fact that, for the cylinder, only 12 adjoint PARTISN computations were required by the 2ndASAM to compute all of the benchmark’s 18 firstorder sensitivities and 224 secondorder sensitivities, in contrast to the 877 PARTISN calculations needed to compute the respective sensitivities using central finite differences, and this number does not include the additional calculations that were required to find appropriate values of the perturbations to use for the central differences.},
doi = {10.1080/00295639.2018.1426899},
journal = {Nuclear Science and Engineering},
number = 2,
volume = 190,
place = {United States},
year = {2018},
month = {4}
}