Input interpretation
At-211 (astatine-211)
Decay properties
half-life | 7.2139 hours (7.2059 to 7.2222 h) mean lifetime | 10.408 hours (10.397 to 10.419 h) decay constant | 2.6688×10^-5 per second specific activity | 76175 TBq/g (terabecquerels per gram) width | 1.757×10^-20 eV (electronvolts) decay modes | ϵ (electron capture) | α (alpha emission) final decay products | Pb-207 (100%)
Decay modes
decay mode | ϵ (electron capture) branching ratio | 58.2% Q-value | 785.36 keV (kiloelectronvolts) daughter nuclide | Po-211 decay mode | α (alpha emission) branching ratio | 41.8% Q-value | 5.98237 MeV (megaelectronvolts) daughter nuclide | Bi-207
Decay chain
Decay chain
Mass properties
atomic number (Z) | 85 mass number (A) | 211 neutron number | 126 atomic mass | 210.987496271 u (unified atomic mass units) mass excess | -11.647148 MeV (megaelectronvolts) binding energy per nucleon | 7.811354 MeV (megaelectronvolts)
Mass properties
Nearby isotopes
Nearby isotopes
Quantum properties
spin parity J^π | 9/2^- (atomic boson)
Quantum properties
Excitations
E_level | spin parity J^π | half-life τ_1/2 | width Δ 674.12 keV (kiloelectronvolts) | 7/2^- | (unknown) | (unknown) 866 keV (kiloelectronvolts) | 7/2^- | (unknown) | (unknown) 947.45 keV (kiloelectronvolts) | 5/2^- | (unknown) | (unknown) 1067.1 keV (kiloelectronvolts) | 13/2^- | 1.4×10^-10 seconds | 3.3×10^-6 eV (electronvolts) 1116.22 keV (kiloelectronvolts) | 3/2^- | 5.7×10^-10 seconds | 8×10^-7 eV (electronvolts) 1123.2 keV (kiloelectronvolts) | 11/2^- or 13/2^- (uncertain) | (unknown) | (unknown) 1270.4 keV (kiloelectronvolts) | 15/2^- or 17/2^- (uncertain) | 1.2×10^-8 seconds | 3.8×10^-8 eV (electronvolts) 1320.6 keV (kiloelectronvolts) | 17/2^- | 7×10^-11 seconds | 7×10^-6 eV (electronvolts) 1355 keV (kiloelectronvolts) | 9/2 or 11/2 or 13/2 (uncertain) | (unknown) | (unknown) 1416.6 keV (kiloelectronvolts) | 21/2^- | 3.51×10^-8 seconds | 1.3×10^-8 eV (electronvolts)