The Effect of Self-Absorption on the Scintillation Properties of ${\rm Ce}^{3+}$ Activated ${\rm LaBr}_{3}$ and ${\rm CeBr}_{3}$

Experimental studies of LaBr
₃
doped with 5%, 10%, 20% and 30% Ce
³⁺
and CeBr
₃
are performed for application in TOF-PET. X-ray excited emission spectra, decay time constants, photoelectron yields and energy resolutions are measured from 100 K to 600 K. The results show a strong temperature and Ce
³⁺
concentration dependence, which is mostly explained by Ce
³⁺
self-absorption. We modeled how self-absorption affects the scintillation pulse shape and what the consequences are for the detector timing resolution. It shows that self-absorption elongates the decay time constant, whilst it does not affect the scintillation rise time.