PARMA: PHITS-based analytical radiation model in the atmosphere - Verification of its accuracy in estimating cosmic radiation doses
Paper in proceeding, 2008

Estimation of cosmic-ray spectra in the atmosphere has been an essential issue in the evaluation of the aircrew doses. We therefore developed an analytical model that can predict the terrestrial neutron, proton, He nucleus, muon, electron, positron and photon spectra at altitudes below 20 km, based on the Monte Carlo simulation results of cosmic-ray propagation in the atmosphere performed by the PHITS code. The model was designated PARMA. In order to examine the accuracy of PARMA in terms of the neutron dose estimation, we measured the neutron dose rates at the altitudes between 20 to 10400 m, using our developed dose monitor DARWIN mounted on an aircraft. Excellent agreement was observed between the measured dose rates and the corresponding data calculated by PARMA coupled with the fluence-to-dose conversion coefficients, indicating the applicability of the model to be utilized in the route-dose calculation.

Aircrew dosimetry


Radiation monitoring

Cosmic ray



T. Sato

Japan Atomic Energy Agency

H. Yasuda

National Institute of Radiological Sciences

M. Takada

National Institute of Radiological Sciences

Takashi Nakamura

Japan Atomic Energy Agency

National Institute of Radiological Sciences

Daiki Satoh

Japan Atomic Energy Agency

A. Endo

Japan Atomic Energy Agency

K. Niita

Research Organization for Information Science and Technology

Lembit Sihver

Chalmers, Applied Physics, Nuclear Engineering

AIP Conference Proceedings

0094-243X (ISSN) 1551-7616 (eISSN)

Vol. 1034 99-102
978-073540559-2 (ISBN)

Subject Categories

Physical Sciences





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