Pm
Promethium-135m
Protons (Z)
61
Neutrons (N)
74
Mass number
135
Half-Life
40.0 s
Abundance
---
Mass
134.925 u
Mass Excess
-69,830.0 keV
Spin
(11/2-)
Discovered
1989
Binding energy per nucleon
8,235 keV
Neutron separation energy
11,141 keV
Proton separation energy
1,473 keV
Decay Mode
- β⁺→Neodymium-135100%
Decay chain
- PmPromethium-135Z 61 · N 7440.0 s
- β⁺100%
- β⁺100%
- β⁺100%
- β⁺100%
- β⁺100%