Pulsed optically stimulated luminescence from α-Al2O3:C using green light emitting diodes (original) (raw)
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Australasian Physical & Engineering Sciences in Medicine, 2009
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Recent advances in dosimetry using the optically stimulated luminescence of Al2O3:C
Radiation Protection Dosimetry, 2004
This paper presents an overview of some very recent developments in optically stimulated luminescence (OSL) dosimetry using aluminium oxide (Al 2 O 3 :C), with special emphasis given to the work of the research group at Oklahoma State University. Some of the advances are: (i) the development of a real-time optical ®bre system for in vivo dosimetry applied to radiotherapy; (ii) the development of a ®bre dosimetry system for remote detection of radiological contaminants in soil; (iii) the characterisation of Al 2 O 3 :C in heavy charged particle ®elds and the study of ionisation density dependence of the OSL from Al 2 O 3 :C; and (iv) fast and separate assessment of beta and gamma components of the natural dose rate in natural sediments. These achievements highlight the versatility of the OSL technique associated with the high-sensitivity of Al 2 O 3 :C for the development of new dosimetry applications.
Comparison between blue and green stimulated luminescence of Al2O3:C
Radiation Measurements, 2010
This paper presents a systematic comparison of OSL signals from Al 2 O 3 :C when stimulated with blue and green light. Al 2 O 3 :C detectors were irradiated with various doses and submitted to various bleaching regimes using yellow, green and blue light. Most of the investigations were carried out using LuxelÔtype detectors used in the commercial LuxelÔ and InLightÔ dosimetry systems (Landauer Inc.). Al 2 O 3 :C single crystals and Al 2 O 3 :C powder were also used to complement the investigations. The results show that, although blue stimulation provides faster readout times (OSL curves that decayed faster) and higher initial OSL intensity than green stimulation, blue stimulation introduced complicating factors. These include incomplete bleaching of the dosimetric trap when the Al 2 O 3 :C detectors are bleached with yellow or green light and the OSL is recorded with blue light stimulation, and an increased residual level due to stimulation of charge carriers from deep traps. The results warrant caution when using blue stimulation to measure the OSL signal from Al 2 O 3 :C detectors, particularly if the doses involved are low and the detectors have been previously exposed to high doses.
Time-resolved optically stimulated luminescence from α-Al2O3:C
Radiation Measurements, 1995
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World Journal of Nuclear Science and Technology, 2012
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Development of a 2D dosimetry system based on the optically stimulated luminescence of Al2O3
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h i g h l i g h t s A 2D dosimetry system based on OSL of Al 2 O 3 was built and demonstrated. Combination of UV and F-center emission is used for fast readout. A special algorithm was developed to correct for slow F-center emission. Potential of measuring 2D dose was demonstrated. Comparison of dose profile with EBT2 and EDR2 film showed good qualitative agreement.
Al2O3:C as a sensitive OSL dosemeter for rapid assessment of environmental photon dose rates
Radiation Measurements, 1997
The use of A1203:C single crystals as optically stimulated luminescence (OSL) dosemeters for rapid assessment of the environmental photon dose rate is proposed. It is shown that AI~O3:C possesses higher OSL sensitivity than TL sensitivity, in TL measurements thermal quenching is a major problem that crucially depends on the heating rate used and, therefore, the all-optical nature of the OSL procedure is an obvious advantage as it obviates the necessity to heat the material thereby avoiding destruction of the luminescence signal. It is demonstrated that the exceptional high OSL sensitivity and the energy response (equal to that of quartz) make A1203:C ideal for measuring the environmental dose rates in connection with luminescence dating and retrospective dosimetry using natural materials and ceramics.