Energy dependence of the supralinearity (f(D)max) of peaks 7 and 8 in the high temperature thermoluminescence of LiF:Mg,Ti (TLD-100) : Interpretation using the Unified Interaction Model

It is demonstrated that the supralinearity of the dose response of glow peaks 7, 8 in the glow curve of LiF:Mg,Ti (TLD-100) are very strongly dependent on photon/electron energy. Previously published data on f(D)max at photon energies of 1.25 MeV, 100 keV and 8.1 keV effective energy coupled with new data at ∼ 540 keV using 90Sr/90Y beta rays reveals that the maximum supralinearity f(D)max decreases from values of ∼200 and ∼30 at 1.25 MeV, through intermediate values at 540 keV and 100 keV, to values of ∼ 30 and ∼3 at 8.1 keV effective energy. The normalized dose response f(D) for all energies is modeled using the Unified Interaction Model and the dependence of f(D)max on energy is interpreted as arising from strong dependence of the relative intensity of localized recombination on particle energy (ionization density).