Naslov
Sensitivity of LiF TL dosemeters in thermal and fast neutron irradiation fields.

Autori
Ranogajec-Komor, Maria ; Osvay, Margit ; Miljanić, Saveta ; Deme, Sandor ; Zaidi, Mohammed

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts / - New Haven (CT), 2004, 83-83

Skup
14th International Conference on Solid State Dosimetry

Mjesto i datum
New Haven (CT), Sjedinjene Američke Države, 27.06.2004. - 02.07.2004

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
LiF; neutron irradiation; LET effect; thermoluminescence

Sažetak
The sensitivity of the most TL dosemeters (expressed as the TL response/absorbed dose) decreases with increasing LET. However, it is known that the 'high temperature peak' (HTP) of LiF detectors increases with increasing LET, while the 'low temperature peak' of LiF (LTP) decreases. There is no agreement in the literature on the linearity of LTP and HTP using high LET radiation field. The reason in most cases is that the gamma background in the mixed field is not taken properly into consideration. TLD-100, MTS-N and TLD-700 dosemeters are widely used and easily available in the every day practice for work place monitoring where sometimes low LET (gamma) and mixed low and high LET (e.g. gamma-neutron) radiation has to be measured. The aim of this study was to examine the change on the structure of the glow curves by increasing dose of neutron radiation, to investigate the linearity of LTP and HTP for TLD-100, TLD-700 and MTS-N LiF dosemeters and to compare the LET sensitivity of these LiF using thermal and fast neutron (14.5 MeV) radiation in mGy dose range. The following irradiations of TLDs were performed: a) gamma with 137Cs source, b) thermal neutron with 238Pu-Be source (fluence rate: 2x107 n/s) using a 20 cm diameter spherical polyethylene moderator, c)14.5 MeV fast neutrons. The gamma component was measured by Al2O3:Mg, Y ceramic TL dosemeters in the thermal neutron irradiation field and by GM counter in the fast neutron irradiation field, respectively. It was found that, while the gamma sensitivity of MTS-N to TLD-100 is about 2.5, the thermal neutron sensitivity differs not so much, i.e. about 1.25. The high temperature TL peak is linear for both kinds of LiF dosemeters in the thermal dose range (1– 150 mSv) investigated. In TLD-100 and TLD-700 also two LET selective peak can be observed after 14.5 MeV neutron irradiation. The linearity of the both peaks in the neutron irradiation field and different LET dependence of the two peaks allows separation of the low and high LET component of the radiation field.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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