Pm

Promethium-149m

Protons (Z)

61

Neutrons (N)

88

Mass number

149

Half-Life

35.0 µs

Abundance

---

Mass

148.919 u

Mass Excess

-75,824.2 keV

Spin

11/2-

Discovered

1966

Binding energy per nucleon

8,260 keV

Neutron separation energy

7,030 keV

Proton separation energy

5,705 keV

Decay Mode

γPromethium-149100%

Decay chain

Promethium-149Z 61 · N 8835.0 µs
γ100%
β⁻100%