Radioactivity Induced in Bones During Radiotherapy Treatment with the Use of 20 MV Accelerator Beam

The induced radioactivity of the elements in bones via nuclear reactions is investigated. High – energy biomedical accelerators are the sources of X-ray and electron beams. Emission of these beams causes appearance of undesired neutron radiation originating from (�� ,n) and (e,e’n) reactions. These reactions also, as well as (n,�� ) reaction, can induce radioactivity in various materials, including the human body. We have focused on neutron capture reactions induced by thermal and epithermal neutrons, because neutron flux is relatively high over the whole treatment room and thus neutrons can react with whole patients’ body. That is why the radioactivity induced by neutrons can be good indicator of an absorbed undesirable neutron dose.