Ce3+-doped scintillating glasses with high light yield and high density are promising candidates for use in electromagnetic calorimeters for particle physics applications. Here, Ce3+-doped glasses with up to 30 mol% Gd2O3 in the system SiO2–B2O3–Al2O3–Gd2O3 have been prepared. Substitutions of Al2O3 by Ga2O3, SiO2 by GeO2 and oxygen by fluorine have been made to increase the density, the resulting effects on optical absorption, luminescence and scintillating properties have been investigated. The glasses made have a high density of 5.0–5.5×103 kgm−3. Substitution of fluorine for oxygen resulted in a large increase in the light yield.

Ce3+-doped scintillating glasses with high light yield and high density are promising candidates for use in electromagnetic calorimeters for particle physics applications. In the present work, Ce3+-doped glasses containing a large amount of Gd2O3 in the system SiO2-B2O3-Al2O3-Gd2O3 have been prepared. Effects of substitution of Al2O3 by Ga2O3, SiO2 by Geo(2) and oxygen by fluorine on the density, optical absorption, luminescence and scintillating properties have been investigated. The glasses have a high density of 5.0-5.5g/cm(3). Substitution of fluorine for oxygen resulted in a large increase in the light yield.

Transparent glass-ceramics have been prepared by heat-treating SiO2-Al2O3-CaO-CaF2 glasses doped with rare earth ions. The samples have been investigated by differential thermal analysis (DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM), UV/Visible spectrometry and fluorescence spectrometry. The precipitated crystalline phase in the glass-ceramics was CaF2. The rare earth dopant ions were found to enter into the CaF2 crystalline phase and give much stronger emission in the glass-ceramics than in the corresponding glass.

Inorganic glasses are a potential source of affordable scintillators for particle physics; however, for application to calorimetry, dense glasses are required, and oxide glasses with the necessary characteristics have proved difficult to produce. Recent work has demonstrated that cerium-doped heavy metal fluoride (HMF) glasses have many of the required properties, although their performance is limited by the fact that CeF3 emission is in the near ultraviolet, close to the band edge for transmission in the glass. The light yield from large blocks of glass is, therefore, reduced by self-absorption. The yield is further reduced when the material is exposed to ionising radiation, which causes the formation of colour centres, increasing absorption at short wavelengths. This work reports on initial studies into the addition of rare earth fluorides to Ce-doped HMF glasses as a means of moving the emission wavelength away from the absorption edge and some developments in the manufacture of dense oxide glasses. A number of co-doped glasses have been made and measurements on transmission, scintillation yield and decay time are presented, showing a strong correlation between yield and decay time.

Transparent glass-ceramics have been prepared by heat-treating 45SiO2–20Al2O3–10CaO–25CaF2 glasses doped with Eu2+ ions (in mol%). The precipitated crystalline phase in the glass-ceramics was CaF2. TEM observation showed the precipitated crystalline phase had a size of 11–18nm and dispersed in the amorphous phase without clustering. Fluorescence measurements showed that Eu2+ ions entered into the CaF2 crystalline phase and gave a much stronger emission in the glass-ceramics than in the corresponding glass.

The emission and excitation spectra as well as the decay kinetics of cerium-doped fluoro-hafnate glasses of various compositions have been studied using vacuum ultraviolet synchrotron radiation excitation. It has been found that iso-valent modifications of the glass composition do not strongly affect the decay kinetics of cerium emission while two-valent oxygen ions create additional quenching centres leading to a decrease of the light yield. It has been shown that the quenching of Ce emission in cerium-doped fluoro-hafnate glasses starts with a process of impact excitation of cerium emission centres. The results show that the dominant mechanism of energy transfer from the matrix to cerium emission centres in fluoride glasses is different for the 315 nm band and the 400 nm band.