Nuclide reference
Zr-95 — Zirconium-95
The half-life of Zr-95 is 64.032 d. Main decay mode: β⁻ decay to Nb-95 (98.92%).
Identification
- Element
- Zirconium (Zr)
- Atomic number Z
- 40
- Mass number A
- 95
- State
- Radioactive
Key quantities
- Half-life
- 64.032 d
- Specific activity
- 7.942e+14 Bq/g
- Gamma constant Γ (H*(10))
- 0.1165 µSv·m²/(MBq·h)
- Dose rate, 1 GBq at 1 m
- ≈ 117 µSv/h
- A1 / A2 for transport (SSR-6, НП-053-16)
- 2 TBq / 0.8 TBq
- D-value (НП-067-24)
- 0.04 TBq
Decay modes
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 756.725 | 54.38 |
| 724.192 | 44.27 |
| 235.69 (Nb-95m) | 0.2842 |
| 16.616 (Nb-95m) · X-ray line | 0.2661 |
| 16.521 (Nb-95m) · X-ray line | 0.1389 |
| 204.116 (Nb-95m) | 0.02628 |
Includes daughter nuclides in equilibrium: Nb-95m (yield per decay of Zr-95); the emitting nuclide is in brackets. Equilibrium is reached in about 27 d.
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| β⁻, E max | 366.87 | 54.46 |
| 399.41 | 44.34 | |
| 887.91 | 1.08 | |
| 1,123.6 | 0.103 |
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.