Pm

Promethium-142

Protons (Z)

61

Neutrons (N)

81

Mass number

142

Half-Life

40.5 s

Abundance

---

Mass

141.913 u

Mass Excess

-81,142.0 keV

Spin

1+

Discovered

1959

Binding energy per nucleon

8,307 keV

Neutron separation energy

8,690 keV

Proton separation energy

4,239 keV

Decay Mode

β⁺77.1%

Decay chain

Promethium-142Z 61 · N 8140.5 s
β⁺100%