Nuclide reference
Er-171 — Erbium-171
The half-life of Er-171 is 7.516 h. Main decay mode: β⁻ decay to Tm-171 (100%).
Identification
- Element
- Erbium (Er)
- Atomic number Z
- 68
- Mass number A
- 171
- State
- Radioactive
Key quantities
- Half-life
- 7.516 h
- Specific activity
- 9.022e+16 Bq/g
- Gamma constant Γ
- —
- A1 / A2 for transport (SSR-6, НП-053-16)
- 0.8 TBq / 0.5 TBq
- D-value (НП-067-24)
- 0.2 TBq
Decay modes
- β⁻ decay → Tm-171 — 100 %
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 308.291 | 64.4 |
| 295.901 | 28.9 |
| 50.742 · X-ray line | 23.71 |
| 111.621 | 20.5 |
| 49.774 · X-ray line | 13.25 |
| 124.017 | 9.1 |
| 116.656 | 2.3 |
| 210.6 | 0.642 |
| 796.55 | 0.64 |
| 907.7 | 0.635 |
Lines of the bare nuclide (ENDF/B-VIII.0), without daughter ingrowth.
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| β⁻, E max | 1,065.8 | 94.4 |
| 1,490.7 | 2.3 | |
| 577.69 | 2.19 | |
| 492.1 | 0.52 |
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.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.