Calculation of the characteristics of clinical high-energy photon beams with EGS5-MPI

17th International Conference on the Use of Computers in Radiation Therapy

物理学;计算机科学

Shimizu, M.^1 ; Morishita, Y.^1 ; Kato, M.^1 ; Kurosawa, T.^1 ; Tanaka, T.^1 ; Takata, N.^1 ; Saito, N.^1

Quantum Radiation Division, National Metrology Institute of Japan (NMIJ), AIST, Tsukuba, Ibaraki 305-8568, Japan^1

关键词: Beam characteristics;    Conversion factor;    High performance computing;    High-energy photon beams;    Message passing interface;    National metrology institute of japans;    Photon energy spectrum;    Primary standards;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/489/1/012023/pdf
DOI  :  10.1088/1742-6596/489/1/012023

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

A graphite calorimeter has been developed as a Japanese primary standard of absorbed dose to water in the high-energy photon beams from a clinical linac. To obtain conversion factors for the graphite calorimeter, the beam characteristics of the high-energy photon beams from the clinical linac at National Metrology Institute of Japan were calculated with the EGS5 Monte Carlo simulation code. To run the EGS5 code on High Performance Computing machines that have more than 1000 CPU cores, we developed the EGS5 parallelisation package EGS5-MPI by implementing a message-passing interface. We calculated the photon energy spectra, which are in good agreement with those previously calculated by D. Sheikh-Bagheri and D. W. O. Rogers (Med. Phys. 29 3). We also estimated the percentage-depth-dose distributions of photon beams from the linac using the calculated photon energy spectra. These calculated percentage-depth-dose distributions were compared with our measured distributions and were found they are in good agreement as well. We will calculate conversion factors for the graphite calorimeter using our results.