Fm

Fermium-249

Protons (Z)

100

Neutrons (N)

149

Mass number

249

Half-Life

1.6 m

Abundance

---

Mass

249.079 u

Mass Excess

73,519.0 keV

Spin

7/2+

Discovered

1960

Binding energy per nucleon

7,462 keV

Neutron separation energy

6,450 keV

Proton separation energy

4,070 keV

Decay Mode

Decay chain

Fermium-249Z 100 · N 1491.6 m
α33%
β⁺64.7%
EC99.88%
α~100%
β⁻~100%
α~100%
α~100%
β⁻100%
α~100%
α100%
β⁻100%
α~100%
α~100%
α99.992%
β⁻97.91%
α100%
β⁻100%
α100%