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Title: Algebraic method for calculating a neutron albedo

Abstract

A neutron albedo from arbitrary homogeneous and finely grained substances is examined on the basis of a new, algebraic, method. In the approximation of an isotropic distribution of incident and reflected neutrons, it is shown that, in the case of thermal neutrons, coherent scattering on individual particles of finely grained media increases only slightly the transport cross section, but, at a given wall thickness, it reduces the albedo because of a decrease in the density of the substance. A significant increase in the albedo is possible only for neutrons of wavelength on the order of dimensions of a powder grain. The angular distribution of reflected neutrons is discussed, and it is proven that a deviation of this distribution from an isotropic one does not lead to a change in the magnitude of the albedo.

Authors:
;  [1]
  1. Joint Institute for Nuclear Research (Russian Federation), E-mail: shab36@nf.jinr.ru
Publication Date:
OSTI Identifier:
21075944
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Atomic Nuclei; Journal Volume: 70; Journal Issue: 2; Other Information: DOI: 10.1134/S106377880702007X; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ALBEDO; ANGULAR DISTRIBUTION; APPROXIMATIONS; COHERENT SCATTERING; CROSS SECTIONS; DENSITY; THERMAL NEUTRONS; THICKNESS; WAVELENGTHS

Citation Formats

Ignatovich, V. K., E-mail: ignatovi@nf.jinr.ru, and Shabalin, E. P. Algebraic method for calculating a neutron albedo. United States: N. p., 2007. Web. doi:10.1134/S106377880702007X.
Ignatovich, V. K., E-mail: ignatovi@nf.jinr.ru, & Shabalin, E. P. Algebraic method for calculating a neutron albedo. United States. doi:10.1134/S106377880702007X.
Ignatovich, V. K., E-mail: ignatovi@nf.jinr.ru, and Shabalin, E. P. Thu . "Algebraic method for calculating a neutron albedo". United States. doi:10.1134/S106377880702007X.
@article{osti_21075944,
title = {Algebraic method for calculating a neutron albedo},
author = {Ignatovich, V. K., E-mail: ignatovi@nf.jinr.ru and Shabalin, E. P.},
abstractNote = {A neutron albedo from arbitrary homogeneous and finely grained substances is examined on the basis of a new, algebraic, method. In the approximation of an isotropic distribution of incident and reflected neutrons, it is shown that, in the case of thermal neutrons, coherent scattering on individual particles of finely grained media increases only slightly the transport cross section, but, at a given wall thickness, it reduces the albedo because of a decrease in the density of the substance. A significant increase in the albedo is possible only for neutrons of wavelength on the order of dimensions of a powder grain. The angular distribution of reflected neutrons is discussed, and it is proven that a deviation of this distribution from an isotropic one does not lead to a change in the magnitude of the albedo.},
doi = {10.1134/S106377880702007X},
journal = {Physics of Atomic Nuclei},
number = 2,
volume = 70,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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