Application of LiF : Mg,Cu,P (MCP-N) thermoluminescent detectors (TLD) for experimental verification of radial dose distribution models

• Autorzy: Gieszczyk W. , Olko P. , Bilski P. , Grzanka L. , Obryk B. , Horwacik T.
• Konferencja: Proceedings of the International Conference on Development and Applications of Nuclear Technologies NUTECH-2011, 11-14 September 2011, Kraków, Poland
• Języki publikacji: EN

Abstrakty

EN

In track structure theory, the radial distribution of dose, D(r), around an ion track plays a fundamental role in predicting the response of biological systems and physical detectors after a dose (or fluence) of ions. According to the formulations of D(r), the local dose at radial distances below 1 nm can reach values as high as 106 Gy. We propose a new method of verifying experimentally the radial dose distribution around alfa-particle tracks, using LiF:Mg,Cu,P (MCP-N) thermoluminescent detectors (TLD) which are able to measure gamma-ray doses in the kGy range via evaluation of their high-temperature TL glow peak structure over the temperature range of 350–550 centigrade. MCP-N detectors were irradiated with Am-241 alfa-particles at fluences ranging from 107 to 1011 particles/cm2, and by Co-60 gamma-ray doses ranging from several Gy up to the MGy. A number N of individual high-temperature TL peaks were analysed in the obtained glow curves by deconvolution, using the GlowFit code. For each of these peaks, an equation relating the intensity, A, of the TL signal obtained after alfa-particle irradiation and after gamma-ray doses, via the dose-frequency function, f alfa(D), was written in the form: A i alfa = integral A i gamma(D)x f alfa (D)dD, i 1,.., N. Using this set of N equations, where A alfa i and A gamma i(D) were known (measured), the single unknown function f alfa(D) was unfolded and converted to D(r). Parametric unfolding and the SAND-II iterative code were applied. While we were able to confirm the 1/r2 dependence of D(r) in agreement with D(r) expressions, we were unable to conclusively evaluate the dependence of D(r) at intermediate ranges of radial distance r. This preliminary result of our unique experimental approach to determine the radial dose distribution around the path of heavy charged particles in LiF detectors, requires further development.

Słowa kluczowe

EN

heavy charged particles; LiF:Mg,Cu,P (MCP-N); radial dose distribution; thermoluminescence; unfolding

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2012
• Tom: Vol. 57, No. 4
• Strony: 507--512
• Opis fizyczny: BIbliogr. 14 poz., rys.

Twórcy

autor

Gieszczyk W.

autor

Olko P.

autor

Bilski P.

autor

Grzanka L.

autor

Obryk B.

autor

Horwacik T.

• The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences (IFJ PAN), 152 Radzikowskiego Str., 31-342 Kraków, Poland, Tel.: [phone], Fax: [phone],

Bibliografia

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