PURPOSE: Class observation of alpha and beta particle paths with a cloud chamber using TV.
DESCRIPTION: Sealed sources of alpha particles and beta particles are used with a small student cloud chamber to observe the paths of alphas and betas. The alpha paths are very distinct and clear, whereas the beta paths are more diffuse. Cosmic ray products or gamma rays are also visible, but less distinct. A TV camera views the "action," which is displayed on a monitor or on the rear projection system in the lecture halls.
The cloud chamber uses alcohol and dry ice to provide an atmosphere of supersaturated alcohol vapor which condenses along the path of the ionizing particle.
REFERENCES: (PIRA 7D30.60)
EQUIPMENT: Student cloud chamber with alpha and beta sources, mounted TV camera and monitor (projector in lecture halls).
SETUP TIME: 1 hour.
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