Bismuth Silicate & Bismuth Germanate ( BSO & BGO )
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| Bismuth Germanate (BGO) | Bismuth Germanate (BGO) | Bismuth Silicate (BSO) |
| Basic Properties | ||
| Crystal | Bi12SiO20 (BSO) | Bi12GeO20 (BGO) |
| Symmetry | Cubic, 23 | Cubic, 23 |
| Melting Point | 900 °C | 930 °C |
| Density | 9.2 g/cm³ | 9.2 g/cm³ |
| Mohs Hardness | 4.5 | 4.5 |
| Transparencey Range | 450 – 7500 nm | 470 – 7500 nm |
| Transmittance at 633 nm | 69% | 67% |
| Refractive Index at 633 nm | 2.54 | 2.55 |
| Dielectric Constant | 56 | 40 |
| Electro-optic Coefficient | r41 = 5 x 10-12 m/V | r41 = 3.4 x 10-12 m/V |
| Resistivity | 5 x 1011W-cm | 8 x 1011W-cm |
| Loss Tangent | 0.0015 | 0.0035 |
| Comparison, BGO, CWO | |||
| Properties of scintillation Crystals | |||
| Crystal | BGO | CWO | |
| Item | Bi4Ge3O12 | CdWO4 | |
| Effective atomic number | 75 | 65 | |
| Density (g/cm³) | 7.13 | 7.90 | |
| Decay constant (ns) | 300 | 5000 | |
| Light output (%) | 12 | 39 | |
| Maximum emission wavelagth (nm) | 480 | 540 | |
| Refractive index | 2.15 | 5.25 | |
| Sensitivity to moisture | None | None | |
| Cleavage | None | Yes | |
| Attenuation coefficient | X-ray 150 KeV | 9.84 | 7.64 |
| (cm-1) | Y-ray 511 KeV | 0.955 | 0.856 |
| Characteristics | Application | ||
| GSO | Short decay time | High performance | |
| Positron CT | |||
| BGO | Better absorption of | Positron CT | |
| Radioactive rays | Detection of high energy | ||
| Because of its large | Partidle in the field of | ||
| Effective atomic number | Fundamental physics | ||
| CWO | Large light output, which enables the use of silicon photo diode |
X-ray CT |
