Thermally assisted OSL: a potent tool for improvement in minimum detectable dose and extension of dose range of Al2O3:C

• Autorzy: Soni A. , Mishra D. R. , Bhatt B. C. , Gupta S. K. , Rawat N. S. , Kulkarni M. S. , Sharma D. N.
• Języki publikacji: EN

Abstrakty

EN

The influence of electron-phonon interaction on the shape of the optically stimulated lumi-nescence decay curve of Al2O3:C has been studied using thermally assisted optically stimulated lumi-nescence (TA-OSL). The minimum detectable dose (MDD) of a phosphor depends on the standard deviation of the background signal which affects the signal-to-noise ratio. The standard deviation of the background signal reduces at lower stimulation light intensity while the readout time increases. Further, measurement at higher temperature enhances the OSL signal with faster decay due to the temperature dependence of photo-ionization cross-section. To achieve the same decay constant and more signal, the temperature of measurement was raised. As a result of lowering the stimulation in-tensity at higher temperature (85°C) the overall MDD of α-Al2O3:C was found to improve by 1.8 times. For extension of dose linearity in higher range, deeper traps were studied by simultaneous ap-plication of CW-OSL and thermal stimulation up to 400°C, using a linear heating rate of 4K/s. By us-ing this method, two well defined peaks at 121°C and 232°C were observed. These TA-OSL peaks have been correlated with two deeper defects which can be thermally bleached at 650°C and 900°C respectively. These deeper defects are stable up to 500°C, so they can store absorbed dose infor-mation even if the sample is inadvertently exposed to light or heat. The dose vs. TA-OSL response from deep traps of α-Al2O3:C was found to be linear up to 10 kGy, thus extending its application for high dose dosimetry.

Słowa kluczowe

EN

decay constant; photo-ionization cross section; thermally assisted OSL (TA-OSL)

• Wydawca: De Gruyter
• Czasopismo: Geochronometria
• Rocznik: 2013
• Tom: Vol. 40, no. 4
• Strony: 258--265
• Opis fizyczny: Bibliogr. 16 poz., wykr.

Twórcy

autor

Soni A.

• Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India-400085

autor

Mishra D. R.

• Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India-400085

autor

Bhatt B. C.

• 2DST Fellow, C/o Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India-400085

autor

Gupta S. K.

• Technical Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India-400085

autor

Rawat N. S.

• Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India-400085

autor

Kulkarni M. S.

• Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India-400085

autor

Sharma D. N.

• Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India-400085

Bibliografia

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Uwagi

EN