Np
Neptunium-239
Protons (Z)
93
Neutrons (N)
146
Mass number
239
Half-Life
2.36 d
Abundance
---
Mass
239.053 u
Mass Excess
49,311.0 keV
Spin
5/2+
Discovered
1940
Binding energy per nucleon
7,561 keV
Neutron separation energy
6,215 keV
Proton separation energy
5,286 keV
Decay Mode
Decay chain
- NpNeptunium-239Z 93 · N 1462.36 d
- β⁻100%
- α~100%
- α~100%
- β⁻100%
- α~100%
- β⁻98.62%
- α100%
- α~100%
- α100%
- α~100%
- β⁻100%
- α~100%
- β⁻100%