Calcium Tungstate (CaWO4)
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Lattice of Calcium Tungstate |
CaWO4 |
CaWO4-Nd, CaWO4-Ce, CaWO4-Pr, CaWO4-Sm, CaWO4-Er, CaWO4-Eu |
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Standard orientations |
(010) - (100) -(001) - (110) - (111) all others on request |
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Structure |
Tetragonal, Scheelit |
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Lattice constants |
a = 5,25 A b = 11,40 A |
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Color |
colorless |
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Comparison, GSO, BGO, CWO, NaJ |
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Properties of scintillation Crystals |
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Crystal Item |
BGO Bi4Ge3O12 |
CWO CdWO4 |
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Effective atomic number |
75 |
65 |
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Density (g/cm³) |
7.13 |
7.90 |
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Decay constant (ns) |
300 |
5000 |
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Light output (%) |
12 |
39 |
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Maximum emission wavelagth (nm) |
480 |
540 |
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Refractive index |
2.15 |
5.25 |
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Sensitivity to moisture |
None |
None |
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Cleavage |
None |
Yes |
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Attenuation coefficient |
X-ray 150 KeV |
9.84 |
7.64 |
(cm-1) |
Y-ray 511 KeV |
0.955 |
0.856 |
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Characteristics |
Application |
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GSO |
Short decay time |
High performance |
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Positron CT |
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BGO |
Better absorption of |
Positron CT |
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Radioactive rays |
Detection of high energy |
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Because of its large |
Partidle in the field of |
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Effective atomic number |
Fundamental physics |
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CWO |
Large light output |
X-ray CT |
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Which enables the use |
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Of silicon photo diode |
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