A Calutron was a mass spectrometer used for separating the isotopes of uranium developed by Ernest O. Lawrence during the Manhattan Project. Its name is a concatenation of Cal. U._tron, in tribute to the University of California, Lawrence's institution. They were implemented for industrial scale uranium enrichment at the Oak Ridge, Tennessee Y-12 plant established during the war, and provided much of the uranium used for the "Little Boy" nuclear weapon which was dropped onto Hiroshima in 1945.

In a mass spectrometer a vaporised quantity of a sample is bombarded with high energy electrons which causes them to become positively charged ions. They are then accelerated and subsequently deflected by magnetic fields. They then collide with a plate, producing a measurable electric current. The mass of the ions can be calculated according to the strength of the field and the charge of the ions.

Schematic diagram of uranium isotope separation in the calutron.

External links

• "The Calutron" (http://www.lbl.gov/Science_Articles/Research_Review/Magazine/1981/81fepi2.html)