Nuclide reference
W-187 — Tungsten-187
The half-life of W-187 is 1 d. Main decay mode: β⁻ decay to Re-187 (100%).
Identification
- Element
- Tungsten (W)
- Atomic number Z
- 74
- Mass number A
- 187
- State
- Radioactive
Key quantities
- Half-life
- 1 d
- Specific activity
- 2.584e+16 Bq/g
- Gamma constant Γ
- —
- A1 / A2 for transport (SSR-6, НП-053-16)
- 2 TBq / 0.6 TBq
- D-value (НП-067-24)
- 0.1 TBq
Decay modes
- β⁻ decay → Re-187 — 100 %
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 685.81 | 33.2 |
| 479.53 | 26.59 |
| 61.141 · X-ray line | 14.61 |
| 72.002 | 13.55 |
| 134.247 | 10.36 |
| 59.718 · X-ray line | 8.447 |
| 618.37 | 7.57 |
| 551.55 | 6.135 |
| 772.87 | 5.02 |
| 625.52 | 1.314 |
Lines of the bare nuclide (ENDF/B-VIII.0), without daughter ingrowth.
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| β⁻, E max | 625.1 | 66.2 |
| 1,310.9 | 16.9 | |
| 692.53 | 5.4 | |
| 538.02 | 5.1 |
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.