Dose equivalent of neutron and induced gamma rays near a medical accelerator

CHEN Yizheng; LI Junli; QIU Rui; WU Zhen; KANG Xi

doi:10.16511/j.cnki.qhdxxb.2016.25.020

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Journal of Tsinghua University(Science and Technology) ›› 2016, Vol. 56 ›› Issue (12) : 1284-1289. DOI: 10.16511/j.cnki.qhdxxb.2016.25.020

PHYSICS AND ENGINEERING PHYSICS

Dose equivalent of neutron and induced gamma rays near a medical accelerator

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Abstract

High energy accelerators are widely used in medicine, but the related radiation shielding calculations are difficult, especially for rapid assessments of the radiation dose in a maze. This study describes typical estimating methods for the dose equivalent of neutron and induced gamma rays in a maze, and calculates the dose equivalent in a multiple-bend maze. The results were compared with Monte Carlo simulations using the Monte Carlo N-particle transport code (MCNP). The methods can accurately estimate the dose equivalent of the neutron and induced gamma rays in the maze, within an order of magnitude of the Monte Carlo simulation results, with underestimates in some cases. Therefore, a safety factor is suggested for practical applications.

Key words

dose equivalent / maze / neutron / induced gamma ray / Monte Carlo simulation

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CHEN Yizheng, LI Junli, QIU Rui, WU Zhen, KANG Xi. Dose equivalent of neutron and induced gamma rays near a medical accelerator[J]. Journal of Tsinghua University(Science and Technology). 2016, 56(12): 1284-1289 https://doi.org/10.16511/j.cnki.qhdxxb.2016.25.020

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