title: Monte Carlo based geometrical model for efficiency calculation of an n-type HPGe detector.
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.
authors.affiliation: 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
authors.forename: Fatima Padilla
authors.initials: FP
authors.lastname: Cabal
authors.forename: Neivy
authors.initials: N
authors.lastname: Lopez-Pino
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Bernal-Castillo
authors.forename: Yisel
authors.initials: Y
authors.lastname: Martinez-Palenzuela
authors.forename: Jimmy
authors.initials: J
authors.lastname: Aguilar-Mena
authors.forename: Katia
authors.initials: K
authors.lastname: D'Alessandro
authors.forename: Yuniesky
authors.initials: Y
authors.lastname: Arbelo
authors.forename: Yasser
authors.initials: Y
authors.lastname: Corrales
authors.forename: Oscar
authors.initials: O
authors.lastname: Diaz