SUFT33: AirKerma Strength and Dose Rate Constant by the Full Monte Carlo Simulations
Abstract
Purpose: In general, the airkerma strength (Sk) has been determined by the energy weighting the photon energy fluence and the corresponding massenergy absorption coefficient or massenergy transfer coefficient. Kerma is an acronym for kinetic energy released per unit mass, defined as the sum of the initial kinetic energies of all the charged particles. Monte Carlo (MC) simulations can investigate the kinetic energy of the charged particles after photo interactions and sum the energy. The Sk of {sup 192}Ir source is obtained in the full MC simulation and finally the dose rate constant Λ is determine. Methods: MC simulations were performed using EGS5 with the microSelectron HDR v2 type of {sup 192}Ir source. The airkerma rate obtained to sum the electron kinetic energy after photoelectric absorption or Compton scattering for transverseaxis distance from 1 to 120 cm with a 10 m diameter air phantom. Absorbed dose in water is simulated with a 30 cm diameter water phantom. The transport cutoff energy is 10 keV and primary photons from the source need two hundred and forty billion in the airkerma rate and thirty billion in absorbed dose in water. Results: Sk is multiplied by the square of the distance in airkerma ratemore »
 Authors:
 Kawasaki Medical School, Kurashiki, Okayama (Japan)
 Graduate School of Health Sciences, Okayama University, Okayama, Okayama (Japan)
 Kawasaki College of Allied Health Professions, Kurashiki, Okayama (Japan)
 Publication Date:
 OSTI Identifier:
 22642283
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Medical Physics; Journal Volume: 43; Journal Issue: 6; Other Information: (c) 2016 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 61 RADIATION PROTECTION AND DOSIMETRY; 60 APPLIED LIFE SCIENCES; ABSORBED RADIATION DOSES; COMPTON EFFECT; COMPUTERIZED SIMULATION; DOSE RATES; ENERGY ABSORPTION; ENERGY TRANSFER; IRIDIUM 192; KERMA; MONTE CARLO METHOD; PHANTOMS; REACTION KINETICS; FUNDAMENTAL INTERACTIONS
Citation Formats
Tsuji, S, Oita, M, and Narihiro, N. SUFT33: AirKerma Strength and Dose Rate Constant by the Full Monte Carlo Simulations. United States: N. p., 2016.
Web. doi:10.1118/1.4956168.
Tsuji, S, Oita, M, & Narihiro, N. SUFT33: AirKerma Strength and Dose Rate Constant by the Full Monte Carlo Simulations. United States. doi:10.1118/1.4956168.
Tsuji, S, Oita, M, and Narihiro, N. 2016.
"SUFT33: AirKerma Strength and Dose Rate Constant by the Full Monte Carlo Simulations". United States.
doi:10.1118/1.4956168.
@article{osti_22642283,
title = {SUFT33: AirKerma Strength and Dose Rate Constant by the Full Monte Carlo Simulations},
author = {Tsuji, S and Oita, M and Narihiro, N},
abstractNote = {Purpose: In general, the airkerma strength (Sk) has been determined by the energy weighting the photon energy fluence and the corresponding massenergy absorption coefficient or massenergy transfer coefficient. Kerma is an acronym for kinetic energy released per unit mass, defined as the sum of the initial kinetic energies of all the charged particles. Monte Carlo (MC) simulations can investigate the kinetic energy of the charged particles after photo interactions and sum the energy. The Sk of {sup 192}Ir source is obtained in the full MC simulation and finally the dose rate constant Λ is determine. Methods: MC simulations were performed using EGS5 with the microSelectron HDR v2 type of {sup 192}Ir source. The airkerma rate obtained to sum the electron kinetic energy after photoelectric absorption or Compton scattering for transverseaxis distance from 1 to 120 cm with a 10 m diameter air phantom. Absorbed dose in water is simulated with a 30 cm diameter water phantom. The transport cutoff energy is 10 keV and primary photons from the source need two hundred and forty billion in the airkerma rate and thirty billion in absorbed dose in water. Results: Sk is multiplied by the square of the distance in airkerma rate and determined by fitting a linear function. The result of Sk is (2.7039±0.0085)*10{sup −11} µGy m{sup 2} Bq{sup −1} s{sup −1}. Absorbed dose rate in water at 1 cm transverseaxis distance D(r{sub 0}, θ{sub 0}) is (3.0114±0.0015)*10{sup −11} cGy Bq{sup −1} s{sup −1}. Conclusion: From the results, dose rate constant Λ of the microSelectron HDR v2 type of {sup 192}Ir source is (1.1137±0.0035) cGy h{sup −1} U{sup −1} by the full MC simulations. The consensus value conΛ is (1.109±0.012) cGy h{sup −1} U{sup −1}. The result value is consistent with the consensus data conΛ.},
doi = {10.1118/1.4956168},
journal = {Medical Physics},
number = 6,
volume = 43,
place = {United States},
year = 2016,
month = 6
}

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