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Title: Neutron-beam-shaping assembly for boron neutron-capture therapy

Abstract

A neutron-beam-shaping assembly consisting of a moderator, a reflector, and an absorber is used to form a therapeutic neutron beam for the boron neutron-capture therapy of malignant tumors at accelerator neutron sources. A new structure of the moderator and reflector is proposed in the present article, and the results of a numerical simulation of the neutron spectrum and of the absorbed dose in a modified Snyder head phantom are presented. The application of a composite moderator and of a composite reflector and the implementation of neutron production at the proton energy of 2.3MeV are shown to permit obtaining a high-quality therapeutic neutron beam.

Authors:
 [1];  [2];  [3]; ;  [2];  [4];  [5];  [2]
  1. University of Science and Technology Houari Boumediene (Algeria)
  2. Zababakhin All-Russian Scientific Research Institute for Technical Physics (VNIITF) (Russian Federation)
  3. Russian Academy of Sciences, Novosibirsk Branch, Nuclear Safety Institute (Russian Federation)
  4. Russian Academy of Sciences, Budker Institute of Nuclear Physics, Siberian Branch (Russian Federation)
  5. Novosibirsk State University (Russian Federation)
Publication Date:
OSTI Identifier:
22614001
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Atomic Nuclei; Journal Volume: 80; Journal Issue: 1; Other Information: Copyright (c) 2017 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ABSORBED RADIATION DOSES; ACCELERATORS; BEAM SHAPING; BORON; COMPUTERIZED SIMULATION; MODERATORS; NEOPLASMS; NEUTRON BEAMS; NEUTRON CAPTURE THERAPY; NEUTRON SOURCES; NEUTRON SPECTRA; PHANTOMS; PROTONS

Citation Formats

Zaidi, L., Kashaeva, E. A., Lezhnin, S. I., Malyshkin, G. N., Samarin, S. I., Sycheva, T. V., Taskaev, S. Yu., E-mail: taskaev@inp.nsk.su, and Frolov, S. A. Neutron-beam-shaping assembly for boron neutron-capture therapy. United States: N. p., 2017. Web. doi:10.1134/S106377881701015X.
Zaidi, L., Kashaeva, E. A., Lezhnin, S. I., Malyshkin, G. N., Samarin, S. I., Sycheva, T. V., Taskaev, S. Yu., E-mail: taskaev@inp.nsk.su, & Frolov, S. A. Neutron-beam-shaping assembly for boron neutron-capture therapy. United States. doi:10.1134/S106377881701015X.
Zaidi, L., Kashaeva, E. A., Lezhnin, S. I., Malyshkin, G. N., Samarin, S. I., Sycheva, T. V., Taskaev, S. Yu., E-mail: taskaev@inp.nsk.su, and Frolov, S. A. Sun . "Neutron-beam-shaping assembly for boron neutron-capture therapy". United States. doi:10.1134/S106377881701015X.
@article{osti_22614001,
title = {Neutron-beam-shaping assembly for boron neutron-capture therapy},
author = {Zaidi, L. and Kashaeva, E. A. and Lezhnin, S. I. and Malyshkin, G. N. and Samarin, S. I. and Sycheva, T. V. and Taskaev, S. Yu., E-mail: taskaev@inp.nsk.su and Frolov, S. A.},
abstractNote = {A neutron-beam-shaping assembly consisting of a moderator, a reflector, and an absorber is used to form a therapeutic neutron beam for the boron neutron-capture therapy of malignant tumors at accelerator neutron sources. A new structure of the moderator and reflector is proposed in the present article, and the results of a numerical simulation of the neutron spectrum and of the absorbed dose in a modified Snyder head phantom are presented. The application of a composite moderator and of a composite reflector and the implementation of neutron production at the proton energy of 2.3MeV are shown to permit obtaining a high-quality therapeutic neutron beam.},
doi = {10.1134/S106377881701015X},
journal = {Physics of Atomic Nuclei},
number = 1,
volume = 80,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2017},
month = {Sun Jan 15 00:00:00 EST 2017}
}
  • This work assesses the feasibility of using a small, safe, and inexpensive keff 0.98 subcritical fission assembly [subcritical neutron multiplier (SCM)] to amplify the treatment neutron beam intensity attainable from a compact deuterium-deuterium (D-D) fusion neutron source delivering [approximately]1012 n/s. The objective is to reduce the treatment time for deep-seated brain tumors to [approximately]1 h. The paper describes the optimal SCM design and two optimal beam-shaping assemblies (BSAs) - one designed to maximize the dose rate and the other designed to maximize the total dose that can be delivered to a deep-seated tumor. The neutron beam intensity amplification achieved withmore » the optimized SCM and BSA results in an increase in the treatment dose rate by a factor of 18: from 0.56 Gy/h without the SCM to 10.1 Gy/h. The entire SCM is encased in an aluminum structure. The total amount of 20% enriched uranium required for the SCM is 8.5 kg, and the cost (not including fabrication) is estimated to be less than $60,000. The SCM power level is estimated at 400 W when driven by a 1012 n/s D-D neutron source. This translates into consumption of only [approximately]0.6% of the initially loaded 235U atoms during 50 years of continuous operation and implies that the SCM could operate continuously for the entire lifetime of the facility without refueling. Cooling the SCM does not pose a challenge; it may be accomplished by natural circulation as the maximum heat flux is only 0.034 W/cm2.« less
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