Input interpretation
Th-224 (thorium-224) | Ac-221 (actinium-221)
Decay properties
| Th-224 | Ac-221 half-life | 810 ms (700 to 920 ms) | 52 ms (49.4 to 54.6 ms) mean lifetime | 1.17 s (1 to 1.34 s) | 75 ms (71.3 to 78.7 ms) decay constant | 0.856 per second | 13 per second specific activity | 2.3×10^9 TBq/g | 3.6×10^10 TBq/g width | 3.9×10^-16 eV | 8.8×10^-15 eV decay modes | α (alpha emission) | 2β^+ (double beta decay) | α (alpha emission) final decay products | Pb-208 (100%) | Pb-206 (0) | Tl-205 (100%)
Decay modes
Th-224
decay mode | α (alpha emission) branching ratio | 100% Q-value | 7.2985 MeV (megaelectronvolts) daughter nuclide | Ra-220 decay mode | 2β^+ (double beta decay) Q-value | -875.3 keV (kiloelectronvolts) daughter nuclide | Ra-224
Ac-221
decay mode | α (alpha emission) branching ratio | 100% Q-value | 7.7836 MeV (megaelectronvolts) daughter nuclide | Fr-217
Radiation shielding
| Th-224 | Ac-221 lead | 24.6 µm | 26.9 µm water | 67.7 µm | 75 µm air | 61.6 mm | 68.3 mm
Decay chain
Th-224
Decay chain Th-224
Ac-221
Decay chain Ac-221
Mass properties
| Th-224 | Ac-221 atomic number (Z) | 90 | 89 mass number (A) | 224 | 221 neutron number | 134 | 132 atomic mass | 224.021466895 u (unified atomic mass units) | 221.015591248 u (unified atomic mass units) mass excess | 19.996285 MeV (megaelectronvolts) | 14.523155 MeV (megaelectronvolts) binding energy per nucleon | 7.667712 MeV (megaelectronvolts) | 7.690539 MeV (megaelectronvolts)
Mass properties
Nearby isotopes
Nearby isotopes
Quantum properties
| Th-224 | Ac-221 spin parity J^π | 0^+ (atomic boson) | 3/2^- (atomic boson) magnetic moment | 0 μ_N | (unknown)
Quantum properties