Nuclide reference
Pa-234m — Protactinium-234m
The half-life of Pa-234m is 1.159 min. Main decay mode: β⁻ decay to U-234 (99.84%).
Identification
- Element
- Protactinium (Pa)
- Atomic number Z
- 91
- Mass number A
- 234
- State
- Radioactive
Key quantities
- Half-life
- 1.159 min
- Specific activity
- 2.565e+19 Bq/g
- Gamma constant Γ
- —
- D-value (НП-067-24)
- —
Decay modes
Main gamma lines
| Energy, keV | Yield, % |
|---|---|
| 1,001.03 | 0.8417 |
| 766.42 | 0.3173 |
| 742.813 | 0.1066 |
| 258.227 | 0.07642 |
| 786.28 | 0.05437 |
| 13.2818 · X-ray line | 0.02712 |
| 16.4784 · X-ray line | 0.0224 |
| 1,737.75 | 0.02129 |
| 1,831.36 | 0.01742 |
| 73.92 | 0.01379 |
Lines of the bare nuclide (ENDF/B-VIII.0), without daughter ingrowth.
Alpha and beta particles
| Radiation | Energy, keV | Yield, % |
|---|---|---|
| β⁻, E max | 2,273.9 | 97.57 |
| 1,229.4 | 1.002 | |
| 1,463.9 | 0.948 | |
| 1,487.6 | 0.059 |
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.