Noninvasive cross section reconstruction with transport theory constraints
Abstract
We consider the inverse problem of identifying the spatially variable absorption and scattering properties of a medium by measuring the exiting radiation when the body is actively interrogated. We formulate this inverse problem as a PDEconstrained optimization problem and solve it iteratively with Newton's method. The constraint is given by the radiative transport equation for neutral particles. Two examples are considered. The first is a dual inclusion domain with no scattering. This problem explores the convergence patterns of the method. The second problem is a central inclusion problem with scattering. This problem explores the optical thickness limit of the method. This optical thickness was determined to be 23 mean free paths. (authors)
 Authors:
 Texas A and M Univ., College Station, TX 778433133 (United States)
 Publication Date:
 Research Org.:
 American Nuclear Society, Inc., 555 N. Kensington Avenue, La Grange Park, Illinois 60526 (United States)
 OSTI Identifier:
 22105835
 Resource Type:
 Conference
 Resource Relation:
 Conference: PHYSOR 2012: Conference on Advances in Reactor Physics  Linking Research, Industry, and Education, Knoxville, TN (United States), 1520 Apr 2012; Other Information: Country of input: France; 13 refs.
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 22 GENERAL STUDIES OF NUCLEAR REACTORS; CARGO; CROSS SECTIONS; MEAN FREE PATH; NEUTRAL PARTICLES; NEWTON METHOD; OPTIMIZATION; SCATTERING; THICKNESS; TRANSPORT THEORY
Citation Formats
Fredette, N., Ragusa, J., and Bangerth, W.. Noninvasive cross section reconstruction with transport theory constraints. United States: N. p., 2012.
Web.
Fredette, N., Ragusa, J., & Bangerth, W.. Noninvasive cross section reconstruction with transport theory constraints. United States.
Fredette, N., Ragusa, J., and Bangerth, W.. 2012.
"Noninvasive cross section reconstruction with transport theory constraints". United States.
doi:.
@article{osti_22105835,
title = {Noninvasive cross section reconstruction with transport theory constraints},
author = {Fredette, N. and Ragusa, J. and Bangerth, W.},
abstractNote = {We consider the inverse problem of identifying the spatially variable absorption and scattering properties of a medium by measuring the exiting radiation when the body is actively interrogated. We formulate this inverse problem as a PDEconstrained optimization problem and solve it iteratively with Newton's method. The constraint is given by the radiative transport equation for neutral particles. Two examples are considered. The first is a dual inclusion domain with no scattering. This problem explores the convergence patterns of the method. The second problem is a central inclusion problem with scattering. This problem explores the optical thickness limit of the method. This optical thickness was determined to be 23 mean free paths. (authors)},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2012,
month = 7
}

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