Investigation of 8 MV X-rays energy spectrum structure of medical linear accelerator
BAI Yan-ling*, XIAO Xue-fu, SHAO Wen-cheng
*Department of Radiation Physics, Third Hospital of Harbin Medical University, Harbin 150081, China Corresponding author:XIAO Xue-fu, Department of Radiation Metrology, China Institute of Atomic Energy, Beijing 102413,China
Abstract：Objective To study the spectrum structure of X-ray and simplify the description method of it. Methods By the general program of Monte Carlo Geant4 to study X-ray spectrum structure and angular distribution of X-ray energy spectrum. Results The results of percentage depth doses and profile curves at different depths of any radiation fields in water phantom calculated by Monte Carlo Geant4 were consistent with the measurements. Conclusions In radiotherapy, X-ray with same nominal energy have very similar dosimetry characteristics, this indicates they have very similar energy spectrum and angular distribution of spectrum, the differences of dosimetric details reflect the different details of the X-ray spectrum structure and angular distribution of X-ray energy spectrum. These studies have very important significances to rapidly build precise virtual source modeling for Monte Carlo calculation based on dose curves measurements in water phantom.
BAI Yan-ling*,XIAO Xue-fu,SHAO Wen-cheng. Investigation of 8 MV X-rays energy spectrum structure of medical linear accelerator[J]. Chinese Journal of Radiation Oncology, 2012, 21(2): 181-184.
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2012, Vol. 21 
