1Overview
Lead tungstate (PbWO₄, PWO) is a fast, very high-density inorganic scintillator developed for high-energy physics calorimetry. Its standout properties are extreme density (8.28 g/cm³), a short scintillation decay time of a few nanoseconds, and excellent radiation hardness. Those qualities made it the crystal of choice for large electromagnetic calorimeters such as the CMS and ALICE detectors at the LHC, where compact, fast, radiation-tolerant absorption of high-energy showers is essential.
The cost of that speed and density is light yield: PbWO₄ emits only a small fraction of one percent of the light of NaI(Tl), so it is paired with high-gain readout (PMTs or avalanche photodiodes) and frequently operated cooled to raise light output. PbWO₄ is non-hygroscopic and mechanically stable, which simplifies handling in large arrays.
Berkeley Nucleonics supplies PbWO₄ as custom crystals and machined elements for calorimetry and fast-timing research. It is a specialist material: choose it when density, speed, and radiation hardness dominate, and when low light output can be accommodated by the readout and operating temperature.
2Specifications
Values are representative of high-energy-physics-grade PbWO₄ drawn from standard published material data. Light yield in particular is strongly temperature dependent; confirm against the specific crystal grade and operating temperature.
| Parameter | Value | Notes |
|---|---|---|
| Material | PbWO₄ (lead tungstate, PWO) | |
| Density | 8.28 g/cm³ | Among the densest practical scintillators; short radiation length (~0.89 cm) |
| Emission maximum | ~420 nm (blue), with a green component | Matches PMT and APD readout |
| Decay constant | ~7-10 ns (dominant fast component) | Very fast; well suited to high-rate environments |
| Refractive index | ~2.2 | At emission maximum |
| Relative light yield | ~0.3-0.4 (NaI(Tl)=100) | Very low; temperature dependent (rises when cooled) |
| Radiation hardness | High | Developed for LHC calorimetry radiation environments |
| Hygroscopic | No | No hermetic seal required |
3Performance
PbWO₄ trades energy resolution and light output for speed, density, and radiation tolerance. Its short radiation length allows compact calorimeter geometries, and its nanosecond-scale decay supports high event rates and good timing. Because light yield is low and temperature dependent, calorimeter systems built from PbWO₄ typically stabilize crystal temperature and use high-gain, low-noise photodetectors to recover adequate signal.
4Typical Applications
- High-energy physics calorimetry: electromagnetic calorimeters for collider and fixed-target experiments
- Fast timing: high-rate detectors where nanosecond decay is required
- Compact high-density absorbers: shower containment where short radiation length matters
- Radiation-hard detection: environments with high integrated dose
5Available Configurations
PbWO₄ is supplied as custom crystals and machined elements for calorimeter arrays and timing detectors. Readout is typically PMT or avalanche photodiode. Contact the ScintIQ team to specify dimensions, surface finish, and readout integration.
| Parameter | Standard / Typical |
|---|---|
| Form factors | Tapered calorimeter crystals, bars, machined custom elements (verify) |
| Readout | PMT or avalanche photodiode (APD); high gain recommended |
| Operating temperature | Controlled; cooling raises light yield (verify per application) |
| Sealing | None required (non-hygroscopic) |
6Request a Quote
PbWO₄ crystals are quoted as custom items for calorimetry and timing applications. Contact the ScintIQ applications team with your geometry, channel count, readout, and operating temperature requirements.
Talk to a ScintIQ Engineer
The BNC applications team can specify PbWO₄ crystal geometry and readout for high-density, fast-timing, radiation-hard detection.