PHOTOTRANSFERRED THERMOLUMINESCENCE (PTTL) IN LIF (MG, CU, P) (GR-200)

The phototransferred thermoluminescence (PTTL) technique is used to re assess doses in various materials. In this work, PTTL properties of Li F (Mg, Cu, P) have been studied. The optimum PTTL signal occurred at a n ultraviolet (UV) exposure of similar to 1770 J m(-2) and corresponde d to (1.0+/-0.3)% of the primary TL signal for gamma doses in the rang e 0.05-4.0 Gy. Whether the ultraviolet irradiation was performed at ro om temperature, 0 degrees C, or liquid-nitrogen temperature did not ma ke any difference to the PTTL signal. A sensitization technique involv ing a 'pre-dose' followed by annealing was then used in an attempt to increase PTTL sensitivity. The PTTL sensitivity showed a big increase as the sensitization dose increased beyond 100 Gy.