Not covered but contact protected surface source with alpha-radiation and soft components. As alpha- particles are emitted without loss of energy, the source is particularly suited to calibrate alpha-detectors, e.g. in combination with alpha-spectroscopy set. Free limit source with design approval, in metallic protective container.
- Alpha-Energies: 5,486 / 5,443 MeV
- Half-life time: 400 a