A TL Dosemeter for Mixed Thermal Neutron and Gamma Fields Based on GR-200 and GR-207 Detectors

Abstract

- A new ENEA dosemeter based on two TL detectors, LiF(Mg,Cu,P) (GR-200) and 7 LiF(Mg,Cu,P) (GR-207), was investigated. The different thermal neutron and gamma sensitivities of the two detectors allow a good dose equivalent estimation in mixed n-γ fields. The higher sensitivity of both detectors as compared with LiF(Mg,Ti) and 7 LiF(Mg,Ti) detectors, currently used at ENEA for routine personal dosimetry, allows a lower dose equivalent threshold to be achieved as well as a better discrimination of the neutron and gamma components of the radiation field. A dose calculation algorithm was developed and assessed by experimental tests performed both at ENEA Institute for Radiation Protection thermal neutron irradiation facility as well as at the IPSN SIGMA facility in Cadarache (France). The intercalibration test supplied the necessary guidelines for future routine dosemeter calibrations. Our results demonstrated that the new dosemeter can easily replace the currently employed dosemeter for mixed thermal neutron and gamma fields in routine personal dosimetry.