Input interpretation
Fr-201 (francium-201)
Decay properties
half-life | 61 ms (milliseconds) (42 to 81 ms) mean lifetime | 88 ms (milliseconds) (69.7 to 106 ms) decay constant | 11 per second specific activity | 3.4×10^10 TBq/g (terabecquerels per gram) width | 7.5×10^-15 eV (electronvolts) decay modes | α (alpha emission) | β^+ (positron emission) final decay products | Os-189 (3.3%) | Au-197 (3%) | Hg-201 (0.06%) | Ir-193 (3×10^-6%) | Re-185 (2×10^-6%) | Ta-181 (5×10^-11%)
Decay modes
decay mode | α (alpha emission) branching ratio | 100% Q-value | 7.5157 MeV (megaelectronvolts) daughter nuclide | At-197 decay mode | β^+ (positron emission) branching ratio | 1% Q-value | 6.646 MeV (megaelectronvolts) daughter nuclide | Rn-201
Radiation shielding
lead | 25.6 µm water | 70.9 µm air | 64.5 mm
Decay chain
Decay chain
Mass properties
atomic number (Z) | 87 mass number (A) | 201 neutron number | 114 atomic mass | 201.003860867 u (unified atomic mass units) mass excess | 3.596375 MeV (megaelectronvolts) binding energy per nucleon | 7.714797 MeV (megaelectronvolts)
Mass properties
Nearby isotopes
Nearby isotopes
Quantum properties
spin parity J^π | 9/2^- (atomic boson)
Quantum properties