Detection of Photoneutrons Induced From Therapeutic Linear Accelerators

Abstract

Recently, in radiotherapy the linear accelerator is used with high energy of photons. This high energy sometimes reaches to 25 MV. The high photon energy produces neutrons when strike by a heavy metal like tungsten, led and iron due to nuclear reaction this phenomenon is called photoneutron. The induced photoneutron is considered undesirable dose delivered to both of tumor and healthy organs of patient, so this requires a degree of accuracy during the treatment to get the lowest possible hazard to the healthy tissues around the tumor. For that reason, the detection of the induced photoneutron inside the room at different points is a must in order to know the energy of it and the achieved doses. According to the energy spectrum of neutrons must measuring more than one energy of the induced photoneutron. In this work we used two techniques for neutron dosimetry; the first one isThermoluminescence dosimetr and the second is Solid State Nuclear