Produção Nacional
Revisado por pares
166mHo: a multi-γ standard for the calibration of Ge spectrometers
2002; Elsevier BV; Volume: 56; Issue: 1-2 Linguagem: Inglês
10.1016/s0969-8043(01)00182-8
ISSN1872-9800
AutoresEstela Maria de Oliveira, José Ubiratan Delgado, Luiz Tauhata, Carlos J. da Silva, Akira Iwahara, R. Poledna, Anselmo Salles Paschoa,
Tópico(s)Radioactivity and Radon Measurements
ResumoEfficiency calibration curves for germanium detectors are usually established by using a large number of standard γ-ray sources of specific radionuclides, that decay with few γ-rays, or radionuclides with complex decay schemes, such as 133Ba or 152Eu. But these multi-γ radionuclides cannot be used alone, because the γ-rays of high intensity are irregularly distributed across the energy spectrum. 166mHo is a more suitable single source for such calibrations, because this radionuclide decays by β−-emission to the excited states of 166Er with the subsequent emission of about 20 strong and well distributed γ-rays ever the energy range 50–1000 keV. Moreover, with a relatively long half-life (1200 yr) and characteristic X-rays between 40 and 50 keV, this nuclide is a good standard for the calibration of germanium detectors. The X- and γ-ray emission probabilities of their main lines need to be known with good accuracy in order to resolve the discrepancies found in the literature. A combination of 4πβ–γ coincidence and X- and γ-ray spectrometric techniques have been used to determine 50 photon emission probabilities.
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