PWO
Lead tungsten is originally dedicated to high energy physics detectors. It combines high radiation hardness with good scintillation properties
Technical parameters
| Physical properties | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| PWO | YAG:Ce | YAP:Ce | LuAG:Ce | CRY 18 | LuAG:Pr | LuAP:Ce | BGO | CRY 19 | |
| Density | 8.28 g/cm3 | 4.57 g/cm3 | 5.37 g/cm3 | 6.73 g/cm3 | 4.5 g/cm3 | 6.73 g/cm3 | 8.34 g/cm3 | 7.13 g/cm3 | 7.1 g/cm3 |
| Hardness by Mohs | 4 | 8.5 | 8.6 | 8.5 | 5.8 | 8.5 | - | 5 | - |
| Index of refraction | 2.17 | 1.82 | 1.95 | 1.84 | 1.79 | 1.84 | - | 2.15 | 1.81 |
| Melting point | 1123 °C | 1970°C | 1875°C | 2020°C | 1980°C | 2043°C | 1960 °C | 1050 °C | 2100°C |
| Thermal expansion | - | 0.8-0.9 x 10-5/K | 0.4-1.1 x 10-5/K | - | - | - | - | 0.7 x 10-5/K | 1.8-10.3 x 10-5/K |
| Crystal structure | tetragonal symetric | cubic | rhombic | cubic | monoclinic | cubic | - | cubic | monoclinic |
| Hygroscopic | NO | NO | NO | NO | NO | NO | NO | NO | NO |
| Scintillation properties | |||||||||
| Wavelength of max. emission | 420 nm | 550 nm | 370 nm | 535 nm | 425 nm | 310 nm | 365 nm | 480 nm | 420 nm |
| Decay constant | 5-15 ns | 70 ns | 25 ns | 70 ns | 45 ns | 20 ns | 18 ns | 300 ns | 41 ns |
| Afterglow | - | <0.005 % at 6 ms | <0.005 % at 6 ms | - | - | - | - | <0.005% at 6 ms | - |
| Radiation length for 511 keV | 0.89 cm | 3.5 cm | 2.7 cm | 1.3 cm | 2.74 cm | 1.3 cm | - | 1.1 cm | 2.1 cm |
| Photon yield at 300 K (27°C) | 15-25 phe/MeV | 30 x 103 Ph/MeV | 25 x 103 Ph/MeV | 25 x 103 Ph/MeV | 30 x 103 Ph/MeV | 15-18 x 103 Ph/MeV | 11 x 103 Ph/MeV | 8-10 x 103 Ph/MeV | 24 x 103 Ph/MeV |
| Integrated light output compared to NaI:Tl | - | 40 % NaI:Tl | 70 % NaI:Tl | 20 % NaI:Tl | 80 % NaI:Tl | 66 % NaI:Tl | - | 15-20 % NaI:Tl | 75 % NaI:Tl |
| Molière radius (RM) | 2.0 cm | - | - | - | - | - | - | - | - |
