Performances of a lightweight collimated γ-ray spectrometer for in-situ surveys

In this study we present the design and the perform ances of Cava-rad system, a portable collimated γ-ray spectrometer based on lead-plate method. The s yst m is calibrated using the full-spectrum analysis method with non-negative lea st square constraint in order to obtain the fundamental standard spectra of background, potassi um, uranium, thorium and cesium. The results are validated by comparing the activity con centration of natural radionuclides K, U and Th measured in 35 test sites with those measured us ing HPGe detectors. The mean discrepancies between in situ survey and laboratory measurements are approximately of 20% for K and for Th and 30% for U.

[1]  M. S. Al-Masri,et al.  Determination of 226Ra contamination depth in soil using the multiple photopeaks method. , 2014, Journal of environmental radioactivity.

[2]  R. Menegazzo,et al.  The worldwide NORM production and a fully automated gamma-ray spectrometer for their characterization , 2012, Journal of Radioanalytical and Nuclear Chemistry.

[3]  Alan J. Cresswell,et al.  The use of difference spectra with a filtered rolling average background in mobile gamma spectrometry measurements , 2009 .

[4]  K. Kearfott,et al.  Demonstration of a collimated in situ method for determining depth distributions using γ-ray spectrometry , 2002 .

[5]  Fazio,et al.  Laboratory application of NaI(Tl) gamma-ray spectrometry to studies of natural radioactivity in geophysics , 2000, Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.

[6]  L. Beccaluva,et al.  PETROGENESIS AND EVOLUTION OF THE EUGANEAN MAGMATIC COMPLEX, VENETO REGION, NORTH-EAST ITALY , 1999 .

[7]  M. Lipoglavšek,et al.  In-situ measurement of Cs distribution in the soil , 1994 .

[8]  H. Wollenberg,et al.  Field determination of uranium and thorium by gamma-ray spectrometry, exemplified by measurements in the Ilmaussaq alkaline intrusion, south Greenland , 1971 .

[9]  S. Verhoeven,et al.  The use of portable equipment for the activity concentration index determination of building materials: method validation and survey of building materials on the Belgian market. , 2014, Journal of environmental radioactivity.