Page 24 - Neutrons for Sciences and Society

Neutrons for Science
V2 rockets. After the war German researchers were barred from all activities involving nuclear energy. Physicists had to wait until 1955 for this restriction to be lifted and a wholly American- built reactor became operational at Garching, close to Munich
in 1957. This reactor, with Professor Maier-Leibnitz as director was initially 1 MW in power. It was attached to the Technical University in Munich, distinct from the reactors in the France and the UK which were installed on CEA (or the UK equivalent) sites, and which were isolated from the universities (with the exception of the CENG at Grenoble). The low power of this reactor limited the range of experiments and Maier-Leibnitz placed an emphasis on developing techniques. Amongst these was the invention of neutron guides which has since been very widely used. These
are the neutron analogues of optical fibres for light, and use total reflection to lead neutrons over distances up to tens of metres from the reactor with very small losses of intensity.
A few years later research institutes more similar to the CEA in France were created at Jülich and Karlsruhe with reactors more powerful than that at Garching. The reactor at Karlsruhe, the first designed and constructed by the Germans, went critical in March 1961, and reached a power of 12 MW in December 1962. The reactor at Jülich which was similar to the British reactor DIDO, was operational in 1962. Initially with a power of 10 MW, this was increased to 15 then 23 MW during the following ten years. There, directed by Tasso Springer, Hans Stiller and Werner Schmatz, all trained at Munich, numerous applications were developed using neutrons to study condensed matter.
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