title: Application of the Monte Carlo method for the efficiency calibration of CsI and NaI detectors for gamma-ray measurements from terrestrial samples.
abstract: Gamma-ray measurements in terrestrial/environmental samples require the use of high efficient detectors because of the low level of the radionuclide activity concentrations in the samples; thus scintillators are suitable for this purpose. Two scintillation detectors were studied in this work; CsI(Tl) and NaI(Tl) with identical size for measurement of terrestrial samples for performance study. This work describes a Monte Carlo method for making the full-energy efficiency calibration curves for both detectors using gamma-ray energies associated with the decay of naturally occurring radionuclides (137)Cs (661keV), (40)K (1460keV), (238)U ((214)Bi, 1764keV) and (232)Th ((208)Tl, 2614keV), which are found in terrestrial samples. The magnitude of the coincidence summing effect occurring for the 2614keV emission of (208)Tl is assessed by simulation. The method provides an efficient tool to make the full-energy efficiency calibration curve for scintillation detectors for any samples geometry and volume in order to determine accurate activity concentrations in terrestrial samples.
authors.affiliation: UR-MDTN, National Center for Nuclear Sciences and Technology, Technopole Sidi Thabet, 2020 Sidi Thabet, Tunisia. souad.baccouche@cnstn.rnrt.tn
authors.forename: S
authors.initials: S
authors.lastname: Baccouche
authors.forename: D
authors.initials: D
authors.lastname: Al-Azmi
authors.forename: N
authors.initials: N
authors.lastname: Karunakara
authors.forename: A
authors.initials: A
authors.lastname: Trabelsi
mesh_terms: D002138:Calibration; D002586:Cesium / Q000528:radiation effects*; D004784:Environmental Monitoring / Q000295:instrumentation* / Q000592:standards; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005720:Gamma Rays; D007454:Iodides / Q000528:radiation effects*; D009010:Monte Carlo Method; D011829:Radiation Dosage; D011868:Radioisotopes / Q000032:analysis*; D011874:Radiometry / Q000295:instrumentation* / Q000592:standards; D012680:Sensitivity and Specificity; D012974:Sodium Iodide / Q000528:radiation effects*; D013051:Spectrometry, Gamma / Q000295:instrumentation* / Q000592:standards; D014159:Transducers
chemical_list: D007454:Iodides; D011868:Radioisotopes; D002586:Cesium; D012974:Sodium Iodide; C040050:cesium iodide