Efficiency calibration for in situ γ-ray measurements on the seabed using Monte Carlo simulations: Application in two different marine environments

E G Androulakaki; C Tsabaris; G Eleftheriou; M Kokkoris; D L Patiris; F K Pappa; R Vlastou

doi:10.1016/j.jenvrad.2016.06.015

Efficiency calibration for in situ γ-ray measurements on the seabed using Monte Carlo simulations: Application in two different marine environments

J Environ Radioact. 2016 Nov:164:47-59. doi: 10.1016/j.jenvrad.2016.06.015. Epub 2016 Jul 13.

Authors

E G Androulakaki¹, C Tsabaris², G Eleftheriou³, M Kokkoris⁴, D L Patiris², F K Pappa³, R Vlastou⁴

Affiliations

¹ Hellenic Centre for Marine Research, Institute of Oceanography, P.O. Box 712, GR 19013, Anavyssos, Greece; National Technical University of Athens, Department of Physics, Zografou Campus, GR 15780, Athens, Greece. Electronic address: frosso.androulakaki@hcmr.gr.
² Hellenic Centre for Marine Research, Institute of Oceanography, P.O. Box 712, GR 19013, Anavyssos, Greece.
³ Hellenic Centre for Marine Research, Institute of Oceanography, P.O. Box 712, GR 19013, Anavyssos, Greece; National Technical University of Athens, Department of Physics, Zografou Campus, GR 15780, Athens, Greece.
⁴ National Technical University of Athens, Department of Physics, Zografou Campus, GR 15780, Athens, Greece.

PMID: 27420593
DOI: 10.1016/j.jenvrad.2016.06.015

Abstract

A new approach for calibrating an in situ detection system for measurements in marine sediments has been developed. The efficiency calibration was deduced on full spectral range by Monte Carlo simulations (MCNP5 code) considering a close detector-seabed geometry set-up. Moreover, the influence of the detection efficiency with respect to the variations of the sediment geological characteristics was studied through Monte Carlo simulations. The results of the theoretical approach were compared with experimental calculations in two different real test cases, yielding a satisfactory agreement (up to 10% and 20% for sites 1 and 2 respectively) in the energy range from 351 keV to 2614 keV. For the experimental measurements, the in situ detection system KATERINA was deployed both in the seawater and on the seabed in two different marine environments. The experimental determinations of the detection efficiency were performed by utilizing the acquired data of the deployments, along with additional necessary laboratory measurements. The adopted approach and the obtained results are discussed.

Keywords: Black Sea; In situ γ-ray measurements; Monte Carlo; NaI(Tl) detector; Sediments.

MeSH terms

Computer Simulation*
Geologic Sediments / analysis
Monte Carlo Method*
Radiation Monitoring / methods*
Seawater / analysis
Spectrometry, Gamma