True coincidence summing corrections in HPGe detectors


HNPS Advances in Nuclear Physics vol. 29 (HNPS2022)
Published: Apr 26, 2023
Keywords:
gamma-spectrometry true coincidence Germanium detectors correction factors Monte-Carlo Simulation
Anastasia Milioni
Theodora Vasilopoulou
Marilia I. Savva
Marios J. Anagnostakis
Ion E. Stamatelatos
Abstract

The true coincidence effect is studied in two High Purity Germanium (HPGe) detectors for a variety of isotopes, source geometries and source to detector configurations, via computational tools based on Monte–Carlo simulations. Τhe upgraded patch of MCNP code MCNP–CP and the 2018 version of PENELOPE, which take into account the decay scheme of each cascade emitter, are used to calculate the Full Energy Peak Efficiency (FEPE) for the corresponding gamma-ray energies. The true coincidence correction (TCC) factor is calculated as the ratio of the FEPE derived for each nuclide taking into consideration the true coincidence effect, to the FEPE estimated without considering the phenomenon. In all cases, a satisfactory agreement is observed between the TCC factors calculated using MCNP–CP and PENELOPE 2018. Moreover, the results of the calculations are compared against experimentally derived efficiency values. The correction factors obtained using the TrueCoinc software are applied on experimentally determined FEPE curves, based on measurements performed using reference sources, and consequently the corrected data are compared against the simulations for the "non-coincidence" case. The results of this work contribute to the validation of the computational tools and codes used to study the true coincidence effect and determine the corresponding correction factors, providing useful data for gamma–spectrometry studies of cascade emitters.

Article Details
  • Section
  • Oral contributions
References
D.S. Andreev, K.I. Erokhina, V.S. Zvonov and I.Kh Lemberg, Instr. Exp. Tech. USSR (English transl.) 15 1358 (1972)
D.S. Andreev, K.I. Erokhina, V.S. Zvonov and I.Kh Lemberg , Bull. Acad. Sci. USSR Phys. Ser. (English transl.) 37 ( 8), 41 (1973)
P. De Felice, P. Angelini, A. Fazio, M. Capogni, Appl . Radiat Isot . 56, 117 (2002), https://doi.org/10.1016/S0969 8043(01)00176 2
T. Vidmar et al., Appl Radiat . Isot 66, 764 (2008) https://doi.org/10.1016/j.apradiso.2008.02.015
F. Salvat, J.M. Fernández Varea, J. Baró and J. Sempau, PENELOPE, an algorithm and computer code for Monte Carlo simulation of electronphoton showers Ciemat (Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas) Technical Report no 799 (1996)
A.N. Berlizov, MCNP CP Upgrade Patch Version 3.2, A correlated particle source extension of a general purpose Monte Carlo N Particle transport code, Institute for Nuclear Research National Academy of Sciences of Ukraine (2012)
X 5 Monte Carlo Team, MCNP A general Monte Carlo N Particle transport code, Version 5, LA UR 03 1987 (2003)
S. Sudar, TRUECOINC, A program for calculation of true coincidence corrections for gamma rays, True Coincidence Program Version 1.01, Institute of Experimental Physics, Kossuth University, Debrecen, Hungary (2000)
S. Padovani, I. Mitsios, M. Anagnostakis, D. Mostacci, Radiat . Eff Defects Solids 173, 794 (2018), https://doi.org/10.1080/10420150.2018.1528605