Abstract
Abstract
This work calculates beam quality correction factors (
) in both modulated and unmodulated proton beams using the Monte Carlo (MC) code
. The latest ICRU 90 recommendations on key data for ionizing-radiation dosimetry were adopted to calculate the electronic stopping powers and to select the mean energy to create an ion pair in dry air (
). For modulated proton beams,
factors were calculated in the middle of a spread-out Bragg peak, while for monoenergetic proton beams they were calculated at the entrance region. Fifteen ionization chambers were simulated. The
factors calculated in this work were found to agree within 0.8% or better with the experimental data reported in the literature. For some ionization chambers, the simulation of proton nuclear interactions were found to have an effect on the
factors of up to 1%; while for some others, perturbation factors were found to differ from unity by more than 1%. In addition, the combined standard uncertainty in the MC calculated
factors in proton beams was estimated to be of the order of 1%. Thus, the results of this work seem to indicate that: (i) the simulation of proton nuclear interactions should be included in the MC calculation of
factors in proton beams, (ii) perturbation factors in proton beams should not be neglected, and (iii) the detailed MC simulation of ionization chambers allows for an accurate and precise calculation of
factors in clinical proton beams.
Funder
European Metrology Programme for Innovation and Research
Subject
Radiology Nuclear Medicine and imaging,Radiological and Ultrasound Technology
Cited by
22 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献