Fr

Francium-208m

Protons (Z)

87

Neutrons (N)

121

Mass number

208

Half-Life

432.0 ns

Abundance

---

Mass

207.998 u

Mass Excess

-1,839.0 keV

Spin

10-

Discovered

2009

Binding energy per nucleon

7,753 keV

Neutron separation energy

7,061 keV

Proton separation energy

493 keV

Decay Mode

γFrancium-208100%

Decay chain

Francium-208Z 87 · N 121432.0 ns
γ100%
α89%
β⁺96.2%
β⁺99.33%
β⁺100%