Fukushima Daiichi nuclear disaster (Unit 2 Reactor) the plant would be decommissioned once the crisis was over. The Japanese government estimates the total amount of radioactivity released into the atmosphere was approximately one-tenth as much as was released during the Chernobyl disaster. Significant amounts of radioactive material have also been released into ground and ocean waters. Measurements taken by the Japanese government 30–50 km from the plant showed caesium-137 levels high enough to cause concern, leading the government to ban the sale of food grown in the area. Tokyo officials temporarily recommended that tap water should not be used to prepare food for infants. In May 2012,
On-Line Isotope Mass Separator more than 60 physics experiments are active there. Radioactive nuclei are produced at ISOLDE by impinging a high energy beam of protons on a stationary target. There are a number of target materials depending on the desired final species. Collisions between the proton beam and the target produce a variety of fragments, which are extracted and filtered to yield the desired isotope. The time required for extraction places a lower limit on the half life of isotopes which can be produced by this method. Once extracted, the isotopes are directed either to one of several detectors, an isotope harvesting area,