Radiation Protection Dosimetry Advance Access originally published online on June 14, 2007
Radiation Protection Dosimetry 2008 128(2):133-145; doi:10.1093/rpd/ncm318
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Undesirable nuclear reactions and induced radioactivity as a result of the use of the high-energy therapeutic beams generated by medical linacs
*Department of Nuclear Physics and Its Application, Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
* Corresponding author: akonefal{at}uranos.cto.us.edu.pl
Received November 30, 2006, amended April 27, 2007, accepted May 1, 2007
In this paper, the problem of undesirable photonuclear, electronuclear and neutron capture reactions taking place in the treatment room during emission of the typical high-energy therapeutic beams from two different medical accelerators, i.e. Primus Siemens and Varian Clinac-2300, is presented. The radioisotopes 187W, 56Mn, 28Al, 57Ni, 38Cl, 57Co and 19Au and the neutron activation of 1H were identified as a consequence of these reactions. Moreover, the increased photon fluence rate behind the door of the accelerator bunker in the operator console room was observed during emission of the 20 MV X-rays from the Varian Clinac-2300 as well as in the case of the 15 MV X-ray beam from the Primus Siemens. No increased radiation was observed during the 6 MV X-ray beam emission. The performed measurements produced evidences on the presence of neutrons in the operator console room during emission of the 15 MV X-ray beam from the Primus Siemens as well as the 20 MV X-rays and the 22 MeV electrons from the Varian Clinac-2300 accelerator.