Bismuth germanate crystal

Cho ZH and Earukhi S (1977) New bismuth germanate crystal — a potential detector for the positron camera application./oMrwa/ of Nuclear Medicine 18 840-844. 

The method described is efficient if the optical thickness is not too large. Examples of growth simulations of bismuth germanate crystals with eulithine and sillenite structure are presented below. Properties of the materials considered are listed in Table 8.1. 

Numerical simulation of the melt growth of oxides and other semitransparent crystals is considered. Specific features of these crystals (internal radiative heat transfer, specular reflection from the crystal side, low thermal conductivity of both the crystal and the melt, the tendency to faceting of the crystallization front) and their effect on the growth process are discussed. An efficient numerical method is described and applied to the study of bismuth germanate crystal growth from the melt. 

A redundant medical PET scanner, a CTI ECAT931/08, was acquired. This comprises 128 detector blocks (Figure 2a), each consisting of four photomultiplier tubes viewing a 30 mm thick crystal of bismuth germanate scintillator approximately 49 x 56 mm2 in area, which is cut into an array of 8 x 4 elements (each approximately 5.6 x 12.9 mm2,... 

The materials that have found particular application for gamma-ray measurements are all inorganic crystals sodium iodide (Nal), caesium iodide (Csl), calcium fluoride (CaF2), bismuth germanate (BGO) and, recently, lanthanum halides. Of these, the first is the most important and the last are materials rapidly gaining in importance. 

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