Fluence-to-dose conversion coefficients for neutrons and protons calculated using the PHITS code and ICRP/ICRU adult reference computational phantoms

The fluence to organ-dose and effective-dose conversion coefficients for neutrons and protons with energies up to 100 GeV was calculated using the PHITS code coupled to male and female adult reference computational phantoms, which are to be released as a common ICRP/ICRU publication. For the calculation, the radiation and tissue weighting factors, w(R) and w(T), respectively, as revised in ICRP Publication 103 were employed. The conversion coefficients for effective dose equivalents derived using the radiation quality factors of both Q(L) and Q(y) relationships were also estimated, utilizing the functions for calculating the probability densities of the absorbed dose in terms of LET (L) and lineal energy (y), respectively, implemented in PHITS. By comparing these data with the corresponding data for the effective dose, we found that the numerical compatibilities of the revised w(R) with the Q(L) and Q(y) relationships are fairly established. The calculated data of these dose conversion coefficients are indispensable for constructing the radiation protection systems based on the new recommendations given in ICRP103 for aircrews and astronauts, as well as for workers in accelerators and nuclear facilities.

[1]  Shaoqun Zeng,et al.  Organ dose calculations by Monte Carlo modeling of the updated VCH adult male phantom against idealized external proton exposure , 2008, Physics in medicine and biology.

[2]  X. Xu,et al.  Fluence-to-dose conversion coefficients for monoenergetic proton beams based on the VIP-Man anatomical model. , 2004, Radiation protection dosimetry.

[3]  V. Taranenko,et al.  Fluence-to-absorbed-dose conversion coefficients for neutron beams from 0.001 eV to 100 GeV calculated for a set of pregnant female and fetus models , 2008, Physics in medicine and biology.

[4]  M. Pelliccioni,et al.  Fluence to Effective Dose Conversion Coefficients for Neutrons up to 10 TeV , 1997 .

[5]  Koji Niita,et al.  Analytical Functions to Predict Cosmic-Ray Neutron Spectra in the Atmosphere , 2006, Radiation research.

[6]  Takashi NAKAMURA,et al.  Development of General-Purpose Particle and Heavy Ion Transport Monte Carlo Code , 2002 .

[7]  Hiroshi Nakashima,et al.  PHITS: A particle and heavy ion transport code system , 2006 .

[8]  T. Nagaoka,et al.  Implementation of Japanese Male and Female Tomographic Phantoms to Multi-particle Monte Carlo Code for Ionizing Radiation Dosimetry , 2006 .

[9]  Yukio Sakamoto,et al.  Validation of the event generator mode in the PHITS code and its application , 2007 .

[10]  K. Niita,et al.  Relativistic nuclear collisions at 10A GeV energies from p+Be to Au+Au with the hadronic cascade model , 1999 .

[11]  N. Spyrou,et al.  Neutron-fluence-to-dose conversion coefficients in an anthropomorphic phantom. , 2005, Radiation protection dosimetry.

[12]  Qingming Luo,et al.  Monte Carlo simulations for external neutron dosimetry based on the visible Chinese human phantom , 2007, Physics in medicine and biology.

[13]  K Niita,et al.  Simulations of an accelerator-based shielding experiment using the particle and heavy-ion transport code system PHITS. , 2005, Advances in space research : the official journal of the Committee on Space Research.

[14]  X. Xu,et al.  Fluence-to-dose conversion coefficients based on the VIP-Man anatomical model and MCNPX code for monoenergetic neutrons above 20 MeV. , 2001, Health physics.

[15]  K. F. Eckerman,et al.  Specific absorbed fractions of energy at various ages from internal photon sources: 6, Newborn , 1987 .

[16]  Hiroshi Nakashima,et al.  A new treatment of radiation behaviour beyond one-body observables , 2007 .

[17]  L. Sihver,et al.  Biological Dose Estimation for Charged-Particle Therapy Using an Improved PHITS Code Coupled with a Microdosimetric Kinetic Model , 2009, Radiation research.

[18]  N Petoussi-Henss,et al.  Organ dose conversion coefficients for voxel models of the reference male and female from idealized photon exposures , 2007, Physics in medicine and biology.

[19]  W E Bolch,et al.  Voxel-based models representing the male and female ICRP reference adult--the skeleton. , 2007, Radiation protection dosimetry.

[20]  X. Xu,et al.  Fluence-to-dose conversion coefficients from monoenergetic neutrons below 20 MeV based on the VIP-Man anatomical model , 2000, Physics in medicine and biology.

[21]  A. Kellerer,et al.  Considerations on a revision of the quality factor. , 1988, Radiation research.

[22]  R. Thomas.  The quality factor in radiation protection , 1987 .

[23]  M. Pelliccioni,et al.  Fluence to Effective Dose Conversion Coefficients for Protons from 5 MeV to 10 TeV , 1997 .

[24]  K Niita,et al.  Analysis of dose-LET distribution in the human body irradiated by high energy hadrons. , 2003, Radiation protection dosimetry.

[25]  Takada,et al.  Analysis of the (N,xN') reactions by quantum molecular dynamics plus statistical decay model. , 1995, Physical review. C, Nuclear physics.

[26]  Lembit Sihver,et al.  Development of PARMA: PHITS-based Analytical Radiation Model in the Atmosphere , 2008, Radiation research.

[27]  H. Schuhmacher,et al.  Quality factors, ambient and personal dose equivalent for neutrons, based on the new ICRU stopping power data for protons and alpha particles , 1995 .

[28]  D. J. Brenner.  Conversion Coefficients for Use in Radiological Protection against External Radiation , 1999 .

[29]  Keith F. Eckerman,et al.  GSF male and female adult voxel models representing ICRP reference man-The present status , 2005 .