New scintillation ceramics for X-ray, $\gamma$ and neutron radiation detectors

A method for producing and the scintillation properties of transparent ceramics of the garnet structural type with the composition (Gd,Me)$_3$Al$_2$Ga$_3$O$_{12}$ (Me=Y,Lu) activated by ions of rare earth elements Ce, Pr, and Tb are described. It is shown that introducing the compositional disorder into the cationic suspension of the compounds can significantly improve their scintillation properties. In terms of the combination of parameters, the scintillators (Gd,Y)$_3$Al$_2$Ga$_3$O$_{12}$:Ce,Tb and (Gd,Y)$_3$Al$_2$Ga$_3$O$_{12}$:Ce,Pr are superior to Gd$_2$O$_2$S:Tb,Ce and (Y,Gd)$_2$O$_2$S:Pr and CsI:Tl for use in computed tomographs (CT) and X-ray scanners (XRS). The scintillator (Gd,Y,Lu)$_3$Al$_2$Ga$_3$O$_{12}$:Ce,Mg provides coincidence time resolution (CTR) of annihilation $\gamma$-quanta (511 keV) of less than 100 ps, which makes it in demand for the creation of positron emission tomographs (PET) with the possibility of additional selection by time-of-flight (TOF). The presence of Gd ions in compounds allows the creation of neutron counters with detector elements both in the form of composites and in the form of transparent elements for recording neutrons in a wide range of the spectrum: from thermal to tens of MeV using both amplitude selection and pulse shape discrimination.