Radiant energy – Invisible radiant energy responsive electric signalling – With heating of luminophors
Patent
1988-07-21
1989-05-02
Fields, Carolyn E.
Radiant energy
Invisible radiant energy responsive electric signalling
With heating of luminophors
2504841, G01T 1115
Patent
active
048271314
ABSTRACT:
A novel apparatus and fully automatic, computer implemented method for making radiation dose measurements using composite glow curve data obtained with a thermoluminescent dosimetry reader wherein such composite glow curve data is composed of the superposition of plural overlapping glow peaks plus instrumental and dosimeter background. The background component of the composite glow curve is subtracted out by using an automatic peak search technique followed by individual chip background subtraction based upon the extrapolation of the background curve under the glow curve by fitting on both sides of the curve outside the region of the peaks. Following background subtraction and automatic identification of low temperature signal limits, the leading edges of higher temperature dosimetric peaks are extrapolated to lower temperatures to subtract from the glow curve a lower temperature dosimetric peak without affecting the higher temperature dosimetric peaks. Computerized deconvolution also is effected automatically by computing initial parameters directly from the glow curve shape and with reduced processing time by applying analytical differentiation to a model equation. The separated peaks are then used to obtain meaningful absorbed dose information including elapsed time between irradiation and read-out.
REFERENCES:
Moscovitch, "Automatic Method for Evaluating Elapsed Time Between Irradiation and Readout in LiF-TLD", Radiation Protection Dosimetry, V. 17 (1986) pp. 165-169.
Furetta et al, "Simultaneous Determination of Dose and Elapsed Time in Accident Dosimetry Using Thermoluminescent Materials", Radiation Protection Dosimetry, V. 17 (1986) pp. 161-164.
Nakajima et al, "On Applicability of TL Fading to Estimation of Time after Irradiation", Health Physics, vol. 16, pp. 782-783, 1968.
Sidran, "Luminescence Dosimetry with Time Lapse Indication", Int. Conf. on Luminescent Dosimetry, 1968.
Horowitz et al, Computerized Glow Curve Deconvolution Applied to High-Dose (10.sup.2 -10.sup.5 Gy) TL Dosimetry, Health Physics Meeting, 1985.
Bacci et al, Analysis of TLD-900 Glow Curves: Results on Single Peak Properties, Radiat. Effects 69, 1983, pp. 127-133.
Moscovitch et al, LiF-TLD Via Computerized Glow Curve Deconvolution into Component Glow Peaks, Midyear Topical Meeting, 1984, pp. 89-96.
Bard, Nonlinear Parameter Estimation, Academic Press, 1974, pp. 94-96.
Moscovitch et al, Computerized Glow Curve Deconvolution Applied to Low Dose Thermoluminescent Dosimetry.
Lucas, Glow-Curve Analysis, Applied Thermoluminescence Dosimetry, 1981, pp. 259-269.
Harshaw brochure, Model 2080 TL Picoprocessor.
Pla et al, A Computerized TLD System, Am. Assoc. Phys. Med., 1983, pp. 462-466.
Zlokazov, Method for an Automatic Peak Search in Gamma-Ray Spectra, Nuclear Instruments and Methods, 1982, pp. 509-519.
Moscovitch et al, LiF Thermoluminescence Dosimetry via Computerised First Order Kinetics Glow Curve Analysis, Radiation Protection Dosimetry, vol. 6, No. 1-4, pp. 157-158.
Fields Carolyn E.
Miller John A.
The Harshaw Chemical Company
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