Fr
Francium-208
Protons (Z)
87
Neutrons (N)
121
Mass number
208
Half-Life
59.1 s
Abundance
---
Mass
207.997 u
Mass Excess
-2,665.0 keV
Spin
7+
Discovered
1964
Binding energy per nucleon
7,757 keV
Neutron separation energy
7,887 keV
Proton separation energy
1,319 keV
Decay Mode
Decay chain
- FrFrancium-208Z 87 · N 12159.1 s
- α89%
- β⁺96.2%
- β⁺99.33%
- β⁺100%