For irradiations with γ-rays, e.g. for material testing or applications in medicine or food industry, HZB operates a cobalt-60 source. Cobalt-60 (60Co) is a radioactive isotope which is generated by the irradiation of natural cobalt-59 with neutrons. The Cobalt-60 decays in nickel-60 by emitting β- and γ-rays. In our set-up the β-rays are absorbed by a steal shielding. The γ-rays are used for irradiations and have an energy of 1.17 MeV and 1.33 MeV. These energies are too small for nuclear reactions.
Properties of the HZB source:
The source consists of 60Co-rods, which are extracted from a lead-shielding during the irradiation.The radiation field is radial, the fluence is adjustable over a wide range (200 Gy/h to 2 Gy/h) by the distance between object under study to the source (1.7 cm bis 1.75 m). The dose is determined by the fluence (distance between specimen and source) and irradiation time. The fluence can be measured by a PTW Unidos E. The geometrical set-up of the source allows the homogenous irradiation of even large objects.
The main applications of the Co-Source are irradiations for sterilization and radiation tests of electronic compounds. E.g. art objects afflicted by mould have been sterilized as well as scientific samples. Electronic compounds are tested for radiation hardness in order to predict their life time in radiative environment like space.
Intensity and construction make the source unique in Germany.