On LiF:Mg,Cu,P and LiF:Mg,Ti phosphors high & ultra-high dose features

Abstract

LiF:Mg,Ti and LiF:Mg,Cu,P are well known thermoluminescence (TL) dosimetry materials since many years. A few years ago their properties seemed well known and it was widely believed that they are not suitable for the measurement of doses above the saturation level of the TL signal, which for both materials occur at about 1 kGy. The high-dose high-temperature TL emission of LiF:Mg,Cu,P observed at the IFJ in 2006, which above 30 kGy takes the form of the so-called TL peak ‘B’, opened the way to use this material for measuring the dose in the high and ultra-high range, in particular for the monitoring of ionizing radiation around the essential electronic elements of high-energy accelerators, also fission and fusion facilities, as well as for emergency dosimetry. This discovery initiated studies of high and ultra-high dose characteristics of both these phosphors, which turned out to be significantly different in many aspects. These studies not only strive to refine the method for measuring high doses based on the observed phenomenon, but also, and perhaps above all, bring us closer to understanding its origin and essence. This manuscript aims to review existing research data on the high and ultra-high dose features of both LiF based phosphors.