Autor(es):
Ferreira, L. F. Requicha
; Ferreira, H. M. N. B. L.
; Veloso, J. F. C. A.
; Santos, J. M. F. dos
Data: 2004
Identificador Persistente: http://hdl.handle.net/10316/4454
Origem: Estudo Geral - Universidade de Coimbra
Assunto(s): Inorganic scintillators; NaI(Tl); Energy non-linearity
Descrição
The response of a YAP, NaI(Tl) and BaF2 scintillators to X-rays with energies around the Y, I, and Ba K-absorption edges, respectively, was investigated. For all the scintillators, the amplitude response follows different linear trends for X-ray energies below and above the respective K-edges, presenting a discontinuity at these energies. An abrupt decrease of about 3%, 5% and 2% were observed in the detector amplitude at the K-edges, for the YAP, the NaI(Tl) and the BaF2 scintillator, respectively, corresponding to a decrease of 0.5±0.1, 1.7±0.3 and 0.8±0.2 keV in the energy calibration line. These discontinuities result in a region within 0.5±0.1, 1.6±0.3 and 0.9±0.2 keV where the X-ray energy cannot be obtained unambiguously. The scintillation yields for X-rays present abrupt decreases of about 3%, 4% and 2%, respectively, at the K-edges. The measured non-linearity effects are significantly larger than those obtained for gaseous and semiconductor detectors. The higher amplitude non-linearity observed in NaI(Tl) is attributed to the larger light yield non-linearity in the electron response of this crystal. http://www.sciencedirect.com/science/article/B6TJM-49N7V56-3/1/6bc7816ad91bca6e857e9a848f8eb8a2