title: Design and fabrication of an in situ gamma radioactivity measurement system for marine environment and its calibration with Monte Carlo method.
abstract: Simulation, design and fabrication of a sealing enclosure is carried out for a NaI(Tl) 2″×2″ detector, to be used as in situ gamma radioactivity measurement system in marine environment. Effect of sealing enclosure on performance of the system in laboratory and marine environment (distinct tank with 10m(3) volume) were studied using point sources. The marine volumetric efficiency for radiation with 1461keV energy (from (40)K) is measured with KCl volumetric liquid source diluted in distinct tank. The experimental and simulated efficiency values agreed well. Marine volumetric efficiency calibration curve is calculated for 60keV to 1461keV energy with Monte Carlo method. This curve indicates that efficiency increasing rapidly up to 140.5keV but then drops exponentially.
authors.affiliation: Faculty of Energy Engineering, Sharif University of Technology, P.O. Box 8639-11365, Tehran, Iran. Electronic address: abdolahnejad@alum.sharif.edu.
authors.forename: Hamed
authors.initials: H
authors.lastname: Abdollahnejad
authors.affiliation: Faculty of Energy Engineering, Sharif University of Technology, P.O. Box 8639-11365, Tehran, Iran.
authors.forename: Naser
authors.initials: N
authors.lastname: Vosoughi
authors.affiliation: Faculty of Physics, University of Isfahan, P.O. Box 81746-73441, Isfahan, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Zare
mesh_terms: D002138:Calibration; D003198:Computer Simulation; D004867:Equipment Design; D006801:Humans; D009010:Monte Carlo Method; D011834:Radiation Monitoring / Q000295:instrumentation / Q000706:statistics & numerical data; D011868:Radioisotopes / Q000032:analysis*; D012623:Seawater / Q000032:analysis; D013051:Spectrometry, Gamma / Q000295:instrumentation* / Q000706:statistics & numerical data; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D011868:Radioisotopes; D014875:Water Pollutants, Radioactive
keywords: Efficiency calibration; In situ gamma spectroscopy; MCNPX; Marine environment; NaI(Tl) detector