Investigation of the properties of composite glow peak 5 in slow-cooled TLD-100

The effects of cooling rate following the 400 °C pre-irradiation anneal on the structure of composite peak 5 following low-ionisation density beta/gamma irradiation are described and analysed in both “slow-cooled” and “normally cooled” samples. Computerised glow curve deconvolution is employed with constrained “peak-shape” parameters deduced from anciliary studies using 4 and 5 eV optical excitation. The ratio of the intensity of peak 5a to peak 5 is studied as a function of cooling rate following the 400 °C anneal. It is demonstrated that “slow-cooling” using a cooling rate of 100Kh-1 increases the relative intensity of glow peak 5a to glow peak 5 from ∼0.1∼0.1 to ∼1∼1, thereby significantly improving the precision of measurement of the ratio 5a/5. The improved precision removes a hurdle impeding the development of the ionisation density discrimination properties of the peak 5a/5 nanodosimeter.