Input interpretation
Md-258 (mendelevium-258)
Decay properties
half-life | 51.5 days (51.14 to 51.85 days) mean lifetime | 74.3 days (73.4 to 74.8 days) decay constant | 1.56×10^-7 per second specific activity | 363 TBq/g (terabecquerels per gram) width | 1.03×10^-22 eV (electronvolts) decay modes | α (alpha emission) | β^- (electron emission) | β^+ (positron emission) final decay products | Pb-206 (100%) | Tl-205 (2×10^-6%) | Pb-208 (2.6×10^-9%) | W-184 (9×10^-12%) | Yb-168 (5×10^-27%) | Er-164 (4×10^-27%) | Dy-160 (2×10^-28%) | Dy-156 (1×10^-30%) | Sm-144 (1×10^-31%) | Ce-140 (1×10^-32%) | Dy-164 (0%) | Er-168 (0%) | Gd-156 (0%) | Hf-176 (0%) | Hf-180 (0%) | Sm-152 (0%) | Yb-172 (0%)
Decay modes
decay mode | α (alpha emission) branching ratio | 100% Q-value | 7.27128 MeV (megaelectronvolts) daughter nuclide | Es-254 decay mode | β^- (electron emission) branching ratio | 0.0015% Q-value | 209 keV (kiloelectronvolts) daughter nuclide | No-258 decay mode | β^+ (positron emission) branching ratio | 0.0015% Q-value | 241 keV (kiloelectronvolts) daughter nuclide | Fm-258
Radiation shielding
lead | 24.5 µm water | 67.3 µm air | 61.2 mm
Decay chain
Decay chain
Mass properties
atomic number (Z) | 101 mass number (A) | 258 neutron number | 157 atomic mass | 258.098431319 u (unified atomic mass units) mass excess | 91.688184 MeV (megaelectronvolts) binding energy per nucleon | 7.409669 MeV (megaelectronvolts)
Mass properties
Nearby isotopes
Nearby isotopes
Quantum properties
spin parity J^π | 8^- (atomic fermion)
Quantum properties