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Title: 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 PDE-constrained 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 2-3 mean free paths. (authors)

Authors:
; ;  [1]
  1. Texas A and M Univ., College Station, TX 77843-3133 (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), 15-20 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 PDE-constrained 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 2-3 mean free paths. (authors)},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2012,
month = 7
}

Conference:
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