Nuclide reference
Y-87 — Yttrium-87
The half-life of Y-87 is 3.325 d. Main decay mode: β⁺ decay / electron capture to Sr-87m (100%).
Identification
- Element
- Yttrium (Y)
- Atomic number Z
- 39
- Mass number A
- 87
- State
- Radioactive
Key quantities
- Half-life
- 3.325 d
- Specific activity
- 1.67e+16 Bq/g
- Gamma constant Γ
- —
- A1 / A2 for transport (SSR-6, НП-053-16)
- 1 TBq / 1 TBq
- D-value (НП-067-24)
- 0.09 TBq
Decay modes
- β⁺ decay / electron capture → Sr-87m — 100 %
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 484.805 | 89.84 |
| 388.531 (Sr-87m) | 85.36 |
| 14.165 · X-ray line | 34 |
| 14.098 · X-ray line | 17.7 |
| 510.999 · annihilation 511 keV | 0.36 |
Includes daughter nuclides in equilibrium: Sr-87m (yield per decay of Y-87); the emitting nuclide is in brackets. Equilibrium is reached in about 20 h. In transient equilibrium a daughter's activity exceeds the parent's, so a yield can be above 100%.
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| β⁺, E max | 451.17 | 0.18 |
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.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.