Input interpretation
At-219 (astatine-219)
Decay properties
half-life | 56 seconds (52.5 to 59.5 s) mean lifetime | 81 seconds (75.8 to 85.8 s) decay constant | 0.012 per second specific activity | 3.4×10^7 TBq/g (terabecquerels per gram) width | 8.1×10^-18 eV (electronvolts) decay modes | α (alpha emission) | β^- (electron emission) final decay products | Pb-207 (100%)
Decay modes
decay mode | α (alpha emission) branching ratio | 97% Q-value | 6.3236 MeV (megaelectronvolts) daughter nuclide | Bi-215 decay mode | β^- (electron emission) branching ratio | 3% Q-value | 1.5663 MeV (megaelectronvolts) daughter nuclide | Rn-219
Decay chain
Decay chain
Mass properties
atomic number (Z) | 85 mass number (A) | 219 neutron number | 134 atomic mass | 219.011161691 u (unified atomic mass units) mass excess | 10.397048 MeV (megaelectronvolts) binding energy per nucleon | 7.720191 MeV (megaelectronvolts)
Mass properties
Nearby isotopes
Nearby isotopes
Quantum properties
spin parity J^π | 5/2^- (atomic boson)
Quantum properties