Raaijmakers C P, Konijnenberg M W, Mijnheer B J, Stecher-Rasmussen F, Verhagen H
The Netherlands Cancer Institute, Amsterdam.
Strahlenther Onkol. 1993 Jan;169(1):18-20.
Neutron beams used for Boron Neutron Capture Therapy (BNCT) are always accompanied by photons. These two irradiation components have different relative biological effectiveness. Therefore it is necessary to determine the neutron and photon absorbed dose in the mixed field separately. All gamma-ray detectors however are also sensitive for neutrons. In this work preliminary results are presented using TLD-700 chips, a Mg(Ar) ionisation chamber and a GM-counter to determine the gamma-ray component in a mixed beam of gamma-rays and neutrons. The results show a good agreement between the GM-counter and the ionisation chamber, indicating a small relative neutron sensitivity (ku) for these detectors. The sensitivity of TLD-700 for thermal neutrons however gives rise to a detector response for which a correction is necessary. The uncertainty however in the relative gamma-ray sensitivity (hu) of the detectors is at this moment too large to determine accurate values of the relative neutron sensitivities.
用于硼中子俘获疗法（BNCT）的中子束总是伴随着光子。这两种辐照成分具有不同的相对生物效应。因此，有必要分别确定混合场中的中子和光子吸收剂量。然而，所有伽马射线探测器对中子也敏感。在这项工作中，展示了使用TLD - 700芯片、Mg(Ar)电离室和盖革计数器来确定伽马射线和中子混合束中伽马射线成分的初步结果。结果表明盖革计数器和电离室之间有良好的一致性，表明这些探测器的相对中子灵敏度（ku）较小。然而，TLD - 700对热中子的灵敏度导致探测器产生需要校正的响应。不过，目前探测器相对伽马射线灵敏度（hu）的不确定性太大，无法确定相对中子灵敏度的准确值。
