Nuclide reference
Ag-108m — Silver-108m
The half-life of Ag-108m is 438 years. Main decay mode: β⁺ decay / electron capture to Pd-108 (91.3%).
Identification
- Element
- Silver (Ag)
- Atomic number Z
- 47
- Mass number A
- 108
- State
- Radioactive
Key quantities
- Half-life
- 438 years
- Specific activity
- 2.796e+11 Bq/g
- Gamma constant Γ
- —
- A1 / A2 for transport (SSR-6, НП-053-16)
- 0.7 TBq / 0.7 TBq
- D-value (НП-067-24)
- 0.04 TBq
Decay modes
- β⁺ decay / electron capture → Pd-108 — 91.3 %
- isomeric transition → Ag-108 — 8.7 %
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 722.907 | 90.84 |
| 433.937 | 90.48 |
| 614.276 | 89.84 |
| 21.177 · X-ray line | 35.22 |
| 21.021 · X-ray line | 18.63 |
| 79.131 | 6.629 |
| 632.98 (Ag-108) | 0.1532 |
| 510.999 (Ag-108) · annihilation 511 keV | 0.04918 |
| 433.96 (Ag-108) | 0.04339 |
| 618.86 (Ag-108) | 0.02274 |
Includes daughter nuclides in equilibrium: Ag-108 (yield per decay of Ag-108m); the emitting nuclide is in brackets. Equilibrium is reached in about 17 min.
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| β⁻, E max | 1,650 (Ag-108) | 8.305 |
| 1,017 (Ag-108) | 0.1532 | |
| β⁺, E max | 900 (Ag-108) | 0.02436 |
For β⁻ and 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.