Influence of readout parameters on TL response, re-usability and residual signal in LiF:Mg,Cu,P.
It has recently been recommended that heating rates do not exceed 10 K.s(-1) and that the maximum temperature of readout should not exceed 265 degrees C for LiF:Mg,Cu,P. In some cases, a decrease of sensitivity in this material in the first of several re-use cycles had been reported. Influence of heating rates up to 30 K.s(-1), duration time up to 40s and maximum readout temperatures up to 270 degrees C on TL response, re-usability and residual signal was investigated. It was found that the maximum readout temperatures above 240 degrees C may lead to the thermoluminscent response decrease in the first several re-use cycles. The readout parameters can be optimised to minimise the residual signal (less than 0.4%) and to retain a constant sensitivity at the same time at high heating rates up to 30 K.s(-1) in a short time (less than 1 min per TL chip) without the necessity of heating above 240 degrees C. A concept of 'efficient residual signal' was put forward to quantify more accurately the real residual signal which affects the precision of the next measurement.
Tang
K
K
Solid Dosimetric Detector and Method Laboratory, Beijing, PR China. Tang@ChinaDML.com
Zhao
J
J
Shen
W
W
Zhu
H
H
Wang
Y
Y
Liu
B
B
D003300:Copper / Q000737:chemistry; D005459:Fluorides / Q000737:chemistry / Q000528:radiation effects*; D006358:Hot Temperature; D018020:Lithium Compounds / Q000737:chemistry / Q000528:radiation effects*; D008163:Luminescent Measurements; D008274:Magnesium / Q000737:chemistry; D010758:Phosphorus / Q000737:chemistry; D011854:Radiochemistry; D012680:Sensitivity and Specificity; D013819:Thermoluminescent Dosimetry / Q000379:methods* / Q000706:statistics & numerical data
D018020:Lithium Compounds; C027651:lithium fluoride; D010758:Phosphorus; D003300:Copper; D008274:Magnesium; D005459:Fluorides