Effect of reader and oven annealing on the glow curve structure and fading of a LiF:Mg,Cu,P TL dosimeter.
The effect of pre-irradiation annealing in an oven at 240 degrees C/10 min (oven anneal) and in a TLD reader at 6 degrees C s(-1), 10 s dwell time at a maximum temperature 240 degrees C (reader anneal), on the glow curve structure of a home made sample of LiF:Mg,Cu,P powder has been investigated. It is shown that on oven annealing the glow peak areas of peaks 2 and 3 increase and that of peak 4 decreases, while on reader annealing the area of peak 4 increases and those of peaks 2 and 3 effectively decrease. Values of fading during a post-irradiation storage of 6 months were measured to be 26% and 12% for samples undergoing oven and reader annealing respectively. To reduce the effect of fading several pre-heats at temperatures of 100, 110, 120 and 130 degrees C for 10 min were investigated and 120 degrees C/10 min was chosen as the optimal condition for pre-heat. It is also observed that when imposing pre-heat thermal treatment on this dosimeter or storing the irradiated dosimeter the height of peak 4 effectively increases while the integral of TL signals remains constant.
Hosseini-Pooya
M
M
National Radiation Protection Department, Iranian Nuclear Regulatory Authority, PO Box 14155-4494, Tehran, Iran. mhpooya@yahoo.com
Jafarizadeh
M
M
D003300:Copper; D001330:Electronic Data Processing; D005459:Fluorides; D006361:Heating; D006801:Humans; D018020:Lithium Compounds; D008274:Magnesium; D010758:Phosphorus; D012680:Sensitivity and Specificity; D013696:Temperature; D013819:Thermoluminescent Dosimetry; D013995:Time
D018020:Lithium Compounds; C027651:lithium fluoride; D010758:Phosphorus; D003300:Copper; D008274:Magnesium; D005459:Fluorides