Monte Carlo based geometrical model for efficiency calculation of an n-type HPGe detector

Fatima Padilla Cabal; Neivy Lopez-Pino; Jose Luis Bernal-Castillo; Yisel Martinez-Palenzuela; Jimmy Aguilar-Mena; Katia D'Alessandro; Yuniesky Arbelo; Yasser Corrales; Oscar Diaz

doi:10.1016/j.apradiso.2010.06.018

Monte Carlo based geometrical model for efficiency calculation of an n-type HPGe detector

Appl Radiat Isot. 2010 Dec;68(12):2403-8. doi: 10.1016/j.apradiso.2010.06.018. Epub 2010 Jun 30.

Authors

Fatima Padilla Cabal¹, Neivy Lopez-Pino, Jose Luis Bernal-Castillo, Yisel Martinez-Palenzuela, Jimmy Aguilar-Mena, Katia D'Alessandro, Yuniesky Arbelo, Yasser Corrales, Oscar Diaz

Affiliation

¹ Instituto Superior de Tecnologias y Ciencias Aplicadas, Quinta de los Molinos Ave. Salvador Allende, esq. Luaces, Plaza de la Revolucion, Ciudad de la Habana, CP 10400, Cuba. fpadilla@instec.cu

PMID: 20643556
DOI: 10.1016/j.apradiso.2010.06.018

Abstract

A procedure to optimize the geometrical model of an n-type detector is described. Sixteen lines from seven point sources ((241)Am, (133)Ba, (22)Na, (60)Co, (57)Co, (137)Cs and (152)Eu) placed at three different source-to-detector distances (10, 20 and 30 cm) were used to calibrate a low-background gamma spectrometer between 26 and 1408 keV. Direct Monte Carlo techniques using the MCNPX 2.6 and GEANT 4 9.2 codes, and a semi-empirical procedure were performed to obtain theoretical efficiency curves. Since discrepancies were found between experimental and calculated data using the manufacturer parameters of the detector, a detail study of the crystal dimensions and the geometrical configuration is carried out. The relative deviation with experimental data decreases from a mean value of 18-4%, after the parameters were optimized.