Nuclide reference
Cs-134 — Caesium-134
The half-life of Cs-134 is 2.0652 years. Main decay mode: β⁻ decay to Ba-134 (100%).
Identification
- Element
- Caesium (Cs)
- Atomic number Z
- 55
- Mass number A
- 134
- State
- Radioactive
Key quantities
- Half-life
- 2.0652 years
- Specific activity
- 4.78e+13 Bq/g
- Gamma constant Γ (H*(10))
- 0.2487 µSv·m²/(MBq·h)
- Dose rate, 1 GBq at 1 m
- ≈ 249 µSv/h
- A1 / A2 for transport (SSR-6, НП-053-16)
- 0.7 TBq / 0.7 TBq
- D-value (НП-067-24)
- 0.04 TBq
Decay modes
- β⁻ decay → Ba-134 — 100 %
- β⁺ decay / electron capture → Xe-134 — 0.0003 %
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 604.721 | 97.62 |
| 795.864 | 85.46 |
| 569.331 | 15.37 |
| 801.953 | 8.688 |
| 563.246 | 8.338 |
| 1,365.19 | 3.017 |
| 1,167.97 | 1.79 |
| 475.365 | 1.477 |
| 1,038.61 | 0.99 |
| 32.193 · X-ray line | 0.4441 |
Lines of the bare nuclide (ENDF/B-VIII.0), without daughter ingrowth.
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| β⁻, E max | 658.11 | 70.17 |
| 88.777 | 27.27 | |
| 415.37 | 2.499 |
For β⁻ the endpoint (maximum) energy of the spectrum is given. ENDF/B-VIII.0.
Related calculators
Other isotopes of this element
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.