Fission foil preparation

Fission foils are prepared by applying a coat of fissile material of the desired thickness on a thin metal backing. Details of severed methods of foil preparation are given in Refs. 29-32. A technique used for the preparation of uranium foils is described here. 

The dipping (or brush-painting) and heating is repeated as many times as necessary to achieve the desired foil thickness. The thickness of the foil is determined by weighing it before and after the uranium deposition or, better yet, by counting the alphas emitted by the uranium isotopes. Most of the alphas come from known. 

U therefore the fraction of this isotope in the uranium must be 

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A thin fission foil was prepared using natural uranium. Calculate the ratio of alpha activities due to the isotopes and The abundance a and half-lives of the three isotopes are... 

Sample preparation. One of the most Important problems to overcome In the detection of alpha particles and In direct fission counting Is the preparation of thin foils or sample deposits. This subject has received considerable attention and has been reviewed by several authors... 

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