The main source of terrestrial gamma-ray radiation exposure to humans comes from 238U, 232Th decay chains and 40K decay. γ-ray spectrometry is a consolidated methodology extensively utilized by many nations for investigating and mapping of natural radioelements. The territory were investigated through γ-ray spectrometry implying measurements utilizing laboratory, portable and airborne instruments in order to realize the thematic maps of radioactivity content and in particular of the abundances of eU , eTh: these concentrations by weight are determined indirectly from 238U and 232Th daughter products (214Bi and 208Tl respectively), that are assumed to be in equilibrium with their parent isotope) and 40K. The Veneto region has 18000 km2 with around 50 different lithological formations and 40% of its territory is covered by mountains and hills while the remaining 60% has a plain geomorphology. Therefore, the survey program was planed taking into consideration the geological, geographical and morphological variability of the territory under investigation and divided in three approaching scales undertaking laboratory, in-situ and airborne measurements following the IAEA guidelines. The Legnaro National Laboratory (LNL) is the national leader for the design and realization of high-resolution γ-ray spectrometers, portable and massive NaI(Tl) detectors. The MCA-Rad γ-ray spectrometry system was designed and built up at LNL for measuring large amount of samples with a minimum wait: these features fit perfectly with the requirements of this project. This system is able to measure any type of materials (solid, liquid, gas), and due to the high efficiency and its geometric symmetry, absolute activity measurements are possible with systematic errors below 5%.
Mapping of Natural Radioelements Using γ-Ray Spectrometry: Veneto Region Case of Study.
FIORENTINI, Giovanni;MANTOVANI, Fabio;SHYTI, Manjola;XHIXHA, Gerti;
2012
Abstract
The main source of terrestrial gamma-ray radiation exposure to humans comes from 238U, 232Th decay chains and 40K decay. γ-ray spectrometry is a consolidated methodology extensively utilized by many nations for investigating and mapping of natural radioelements. The territory were investigated through γ-ray spectrometry implying measurements utilizing laboratory, portable and airborne instruments in order to realize the thematic maps of radioactivity content and in particular of the abundances of eU , eTh: these concentrations by weight are determined indirectly from 238U and 232Th daughter products (214Bi and 208Tl respectively), that are assumed to be in equilibrium with their parent isotope) and 40K. The Veneto region has 18000 km2 with around 50 different lithological formations and 40% of its territory is covered by mountains and hills while the remaining 60% has a plain geomorphology. Therefore, the survey program was planed taking into consideration the geological, geographical and morphological variability of the territory under investigation and divided in three approaching scales undertaking laboratory, in-situ and airborne measurements following the IAEA guidelines. The Legnaro National Laboratory (LNL) is the national leader for the design and realization of high-resolution γ-ray spectrometers, portable and massive NaI(Tl) detectors. The MCA-Rad γ-ray spectrometry system was designed and built up at LNL for measuring large amount of samples with a minimum wait: these features fit perfectly with the requirements of this project. This system is able to measure any type of materials (solid, liquid, gas), and due to the high efficiency and its geometric symmetry, absolute activity measurements are possible with systematic errors below 5%.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
