DOSIMETRIC CHARACTERISTICS OF LIFMG,CU,P PHOSPHORS - A TRACK STRUCTURE INTERPRETATION

New sintered LiF:Mg,Cu,P detectors with different concentrations of Cu and P are being investigated in this laboratory. These detectors are about 10-30 times more sensitive than LiF:Mg.Ti to gamma ray (Co-60, C s-137) doses and, unlike LiF:Mg,Ti, show no supralinearity up to satur ation above 200 Gy of gamma rays, thus being amenable to a 1-hit inter pretation, in terms of Katz's track structure theory. Values of model parameters. E(o) = 200 Gy and a(o) = 20 nm, were estimated after fitti ng the 1-bit expression to a number of measured X ray and gamma ray do se responses and fitting to the reported measurements of relative effi ciency of LiF:Mg,Cu,P after proton and alpha particle irradiations. Th e gamma ray dose response of LiF:Mg,Ti (e.g. peak 5 in TLD-700) can be described by a mixture of 1-hit and 2-hit expressions, but for model interpretations of exposures to low energy ions, only the 1-hit 'trap' (estimated values: E(o) = 600 Gy, a(o) = 20 nm) need be considered. T hus, a quantitative model basis is provided for interpreting the respo nse of LiF:Mg,Cu,P to heavy charged particles and neutrons against the responses of 'classic' LiF:Mg,Ti to the same radiations.