Nuclide reference
Xe-133 — Xenon-133
The half-life of Xe-133 is 5.243 d. Main decay mode: β⁻ decay to Cs-133 (100%).
Identification
- Element
- Xenon (Xe)
- Atomic number Z
- 54
- Mass number A
- 133
- State
- Radioactive
Key quantities
- Half-life
- 5.243 d
- Specific activity
- 6.928e+15 Bq/g
- Gamma constant Γ (H*(10))
- 0.01681 µSv·m²/(MBq·h)
- Dose rate, 1 GBq at 1 m
- ≈ 16.8 µSv/h
- A1 / A2 for transport (SSR-6, НП-053-16)
- 20 TBq / 10 TBq
- D-value (НП-067-24)
- 3 TBq
Decay modes
- β⁻ decay → Cs-133 — 100 %
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 80.997 | 38 |
| 30.972 · X-ray line | 26.03 |
| 30.625 · X-ray line | 14.1 |
| 79.623 | 0.27 |
| 160.613 | 0.066 |
| 302.853 | 0.0048 |
| 383.851 | 0.0024 |
| 223.234 | 0.00012 |
Lines of the bare nuclide (ENDF/B-VIII.0), without daughter ingrowth.
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| β⁻, E max | 346.4 | 99 |
| 266.78 | 0.81 |
For β⁻ the endpoint (maximum) energy of the spectrum is given. ENDF/B-VIII.0.
Related calculators
Reference data vs computed valuesHalf-life, gamma lines and D-value are reference data (ENDF/B-VIII.0, НП-067-24).Gamma constant Γ is H*(10) at 1 m computed from ICRP-107 spectra (NIST µ_en/ρ, ICRP-74 Table A.21) including short-lived progeny in equilibrium (e.g. Cs-137/Ba-137m, Ra-226 series); specific activity uses molar mass M ≈ mass number A.Dose rate example: point source, no shielding or scatter, Ḣ = Γ·A/r².K-series X-ray energies are from NIST SRD 128 (Deslattes et al., 2003): in ENDF/B-VIII.0 they are given to 1 % and shifted by up to 0.7 keV for heavy elements. L-series lines and all yields are ENDF/B-VIII.0.