Nuclide reference
Cf-253 — Californium-253
The half-life of Cf-253 is 17.81 d. Main decay mode: β⁻ decay to Es-253 (99.69%).
Identification
- Element
- Californium (Cf)
- Atomic number Z
- 98
- Mass number A
- 253
- State
- Radioactive
Key quantities
- Half-life
- 17.81 d
- Specific activity
- 1.072e+15 Bq/g
- Gamma constant Γ
- —
- A1 / A2 for transport (SSR-6, НП-053-16)
- 40 TBq / 0.04 TBq
- D-value (НП-067-24)
- 0.4 TBq
Decay modes
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 20.9232 · X-ray line | 11.44 |
| 16.0139 · X-ray line | 10.13 |
| 46.4 | 0.09949 |
Lines of the nuclide itself (ENDF/B-VIII.0).
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| α | 5,980 | 0.2936 |
| 5,920 | 0.01643 | |
| β⁻, E max | 240.6 | 50 |
| 287 | 50 | |
| 891.2 (Cm-249) | 0.2999 |
For β⁻ the endpoint (maximum) energy of the spectrum is given. ENDF/B-VIII.0. Includes daughter nuclides in equilibrium: Cm-249 (yield per decay of Cf-253); the emitting nuclide is in brackets. Equilibrium is reached in about 7.5 h.
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.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.