Nuclide reference
Hg-203 — Mercury-203
The half-life of Hg-203 is 46.594 d. Main decay mode: β⁻ decay to Tl-203 (100%).
Identification
- Element
- Mercury (Hg)
- Atomic number Z
- 80
- Mass number A
- 203
- State
- Radioactive
Key quantities
- Half-life
- 46.594 d
- Specific activity
- 5.108e+14 Bq/g
- Gamma constant Γ (H*(10))
- 0.04132 µSv·m²/(MBq·h)
- Dose rate, 1 GBq at 1 m
- ≈ 41.3 µSv/h
- A1 / A2 for transport (SSR-6, НП-053-16)
- 5 TBq / 1 TBq
- D-value (НП-067-24)
- 0.3 TBq
Decay modes
- β⁻ decay → Tl-203 — 100 %
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 279.195 | 81.56 |
| 72.874 · X-ray line | 8.094 |
| 70.833 · X-ray line | 4.798 |
Lines of the bare nuclide (ENDF/B-VIII.0), without daughter ingrowth.
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| β⁻, E max | 212.9 | 100 |
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.