Pa

Protactinium-229m

Protons (Z)

91

Neutrons (N)

138

Mass number

229

Half-Life

420.0 ns

Abundance

---

Mass

229.032 u

Mass Excess

29,909.0 keV

Spin

3/2-

Discovered

1982

Binding energy per nucleon

7,630 keV

Neutron separation energy

7,086 keV

Proton separation energy

4,151 keV

Decay Mode

γProtactinium-229100%

Decay chain

Protactinium-229Z 91 · N 138420.0 ns
γ100%
EC99.51%
α100%
β⁻100%
α~100%
α~100%
α99.992%
β⁻97.91%
α100%
β⁻100%
α100%