La

Lanthanum-139

Protons (Z)

57

Neutrons (N)

82

Mass number

139

Half-Life

Stable

Abundance

99.91119%

Mass

138.906 u

Mass Excess

-87,222.4 keV

Spin

7/2+

Discovered

1924

Binding energy per nucleon

8,378 keV

Neutron separation energy

8,780 keV

Proton separation energy

6,250 keV

Decay Mode

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