Single Crystalline Scintillators Research Articles

New scintillators for X-ray computed tomography

The conversion of X-ray radiation to visible light can be performed by luminescent materials. This effect finds an attractive application in X-ray computed tomography (XCT). The centre of the XCT system with a solid state detector arrangement is the luminescent material coupled to a photosensitive diode. The requirements for efficient luminescent materials are: high X-ray absorption, high light output, fast decay time, and low afterglow. The dominant single crystalline scintillators which meet these specifications, at least in part, are CsI:T1, CdWO 4. and ZnWO 4. Recently, polycrystalline scintillators such as rare earth-doped gadolinium oxysulphide, Gd 2O 2 S:RE, and yttrium-gadolinium oxide, (Y,Gd) 2O 3:RE have been created. These scintillators exhibit high chemical stability. Homogeneous incorporation of rare earth (RE) activators as well as other chemical additives is achieved by controlled ceramic processing.

On the axial distribution of light output in cylindrical scintillation detectors

Abstract The effect of the side surface smoothness on the axial distribution of the light output has been studied for detectors based on alkali halide single crystalline and polycrystalline scintillators with a height-diameter ratio L / D ⪢ 1. It has been shown that an axial inhomogeneity ( δC ) of the light output produces a noticeable effect on the energy resolution at | δC | > 2% and depends upon the ratio L / D . A mechanism of equalization for the light output distribution has been suggested.