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Glossary

Englischsprachiges Glossar

minimum requirementsshow / hide

The minimum requirements primarily relate to the effective containment zone (ECZ) in the relevant areas. If not all the minimum requirements are met in line with Section 23 of the Site Selection Act, an area is unsuitable for disposing of high-level radioactive waste. The minimum requirements in line with Section 23 of the Site Selection Act are rock permeability, the thickness of the effective containment zone, a minimum depth in the effective containment zone, the area of the disposal site and maintaining the barrier effect. The Site Selection Act provides details about the individual requirements.

moderatorshow / hide

In a nuclear reactor, a moderator serves to slow free neutrons produced in the reactor core during the fission process. Similar to billiard balls, neutrons collide with the nuclei of the moderator and thus give off part of their kinetic energy. Since the largest energy transfers occur in the elastic collisions of two equally heavy particles, light atoms such as hydrogen (in the form of water or polyethylene) and carbon (in the form of graphite) are mostly used as moderator. The slowed neutrons are better suitable for both continuing the fission in the reactor core and carrying out scientific experiments in a research reactor.

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