Input interpretation
Ac-227 (actinium-227)
Decay properties
half-life | 21.772 years (21.764 to 21.78 yr) mean lifetime | 31.41 years (31.398 to 31.423 yr) decay constant | 1.0095×10^-9 per second specific activity | 2.6779 TBq/g (terabecquerels per gram) width | 4.6055×10^-25 eV (electronvolts) decay modes | β^- (electron emission) | α (alpha emission) final decay products | Pb-207 (100%) | Tl-205 (9×10^-10)
Decay modes
decay mode | β^- (electron emission) branching ratio | 98.62% Q-value | 44.765 keV (kiloelectronvolts) daughter nuclide | Th-227 decay mode | α (alpha emission) branching ratio | 1.38% Q-value | 5.04219 MeV (megaelectronvolts) daughter nuclide | Fr-223
Radiation shielding
lead | 7.48 µm portland concrete | 19 µm water | 35.6 µm air | 31.7 mm
Decay chain
Decay chain
Mass properties
atomic number (Z) | 89 mass number (A) | 227 neutron number | 138 atomic mass | 227.027752127 u (unified atomic mass units) mass excess | 25.850941 MeV (megaelectronvolts) binding energy per nucleon | 7.650701 MeV (megaelectronvolts)
Mass properties
Nearby isotopes
Nearby isotopes
Quantum properties
spin parity J^π | 3/2^- (atomic boson) magnetic moment | 1.1 μ_N electric quadrupole moment | 1.7 eb (electron barns)
Quantum properties
Excitations
E_level | spin parity J^π | half-life τ_1/2 | width Δ 27.37 keV (kiloelectronvolts) | 3/2^+ | 3.83×10^-8 seconds | 1.19×10^-8 eV (electronvolts) 29.98 keV (kiloelectronvolts) | 5/2^- | (unknown) | (unknown) 46.35 keV (kiloelectronvolts) | 5/2^+ | (unknown) | (unknown) 74.14 keV (kiloelectronvolts) | 7/2^- | (unknown) | (unknown) 84.55 keV (kiloelectronvolts) | 7/2^+ | (unknown) | (unknown) 109.94 keV (kiloelectronvolts) | 9/2^+ | (unknown) | (unknown) 126.86 keV (kiloelectronvolts) | 9/2^- | (unknown) | (unknown) 148 keV (kiloelectronvolts) | (unknown) | (unknown) | (unknown) 160 keV (kiloelectronvolts) | (unknown) | (unknown) | (unknown) 187.32 keV (kiloelectronvolts) | 11/2^+ | (unknown) | (unknown)