Calcium Tungstate ( CaWO4 )

Calcium Calcium Calcium
Lattice of Calcium Tungstate CaWO4 CaWO4-Nd, CaWO4-Ce, CaWO4-Pr,
CaWO4-Sm, CaWO4-Er, CaWO4-Eu
     
Standard orientations (010) - (100) -(001) - (110) - (111) all others on request  
Structure Tetragonal, Scheelit  
Lattice constants a = 5,25 A b = 11,40 A  
Color colorless  
Comparison, GSO, BGO, CWO, NaJ      
Properties of scintillation Crystals      
Crystal Item BGO Bi4Ge3O12 CWO 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 X-ray CT  
  Which enables the use    
  Of silicon photo diode [nbsp