Auto calibration and determination of matrices covariance measurements of energy in gamma spectroscopy.

Author(s)

Theotonio Mendes Pauliquevis Junior

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Física (IF/SBI)
• Defense date: 2000-09-14

Examining board members

Otaviano Augusto Marcondes Helene; Mauro da Silva Dias; Thereza Borello Lewin

• Advisor: Otaviano Augusto Marcondes Helene

Abstract

We measured 21 gamma-ray energies from 57Co, 60Co, 133Ba, 137Cs and 192Ir decay, with a 75 cm3 HPGe detector. The data analysis was performed usin a self calibration procedure, based on the Least Square Method, where experimental and input data are included in a single step. As result of this statistical procedure, 309 other gamma-ray energies not measured, but covariant with the measured ones, as well the covariance matrix were updated. Some transitions got a variance reduction over than 80% when compared with the bibliography, and of 50% when compared with the reanalyzed data that consider all the covariance matrix. (AU)