Ambient dose equivalent measurement with a CsI(Tl) based electronic personal dosimeter

• Published in: Nuclear engineering and technology 2019, 51(8), , pp.1991-1997
• Main Authors: Park, Kyeongjin, Kim, Jinhwan, Lim, Kyung Taek, Kim, Junhyeok, Chang, Hojong, Kim, Hyunduk, Sharma, Manish, Cho, Gyuseong
• Format: Article
• Language: English
• Subjects: Ambient dose equivalent; CsI(Tl) scintillator; Electronic personal dosimeter; G(E) function; PIN diode; 원자력공학
• ISSN: 1738-5733; 2234-358X
• DOI: 10.1016/j.net.2019.06.017

In this manuscript, we present a method for the direct calculation of an ambient dose equivalent (H*(10)) for the external gamma-ray exposure with an energy range of 40 keV to 2 MeV in an electronic personal dosimeter (EPD). The designed EPD consists of a 3×3 mm2 PIN diode coupled to a 3×3×3 mm3 CsI (Tl) scintillator block. The spectrum-to-dose conversion function (G(E)) for estimating H*(10) was calculated by applying the gradient-descent method based on the Monte-Carlo simulation. The optimal parameters for the G(E) were found and this conversion of the H*(10) from the gamma spectra was verified by using 241Am, 137Cs, 22Na, 54Mn, and 60Co radioisotopes. Furthermore, gamma spectra and H*(10) were obtained for an arbitrarily mixed multiple isotope case through Monte-Carlo simulation in order to expand the verification to more general cases. The H*(10) based on the G(E) function for the gamma spectra was then compared with H*(10) calculated by simulation. The relative difference of H*(10) from various single-source spectra was in the range of ±2.89%, and the relative difference of H*(10) for a multiple isotope case was in the range of ±5.56%.