Two different detectors both using thin cracked-ethylene foils will be made. One detector consists of a low-pressure gas cell sealed at either end with aluminized ethylene foils about 10 micro grams per square centimeter thick. Light generated when the proton beam traverses the gas will be viewed through a side window; the intensity of the light as measured with a photomultiplier or photodiode and associated electronics will indicate the ion beam intensity. For the other detector electrons ejected from a single aluminized foil will be magnetically deflected to one side where they will be detected with an electron multiplier; the electron current will indicate the beam intensity. Both detectors depend on the fact that thin ethylene foils have exceptionally long lifetimes under particle bombardment. These detectors will be lineart direct reading, easy to calibrate, and will not interfere with the other uses of the target chamber.
