Diffusion Cloud Chamber

Dry ice causes severe cold burns on contact. Always wear cryogenic gloves when handling. Never place dry ice in sealed containers as sublimating CO₂ can cause explosive pressure buildup.

Follow institutional radiation safety protocols. Use only licensed, sealed sources. Never point sources at people. Store sources in designated shielded containers when not in use.

Purpose

Charged particles leave visible condensation trails in supersaturated alcohol vapor, allowing direct observation of alpha particles, beta particles, and cosmic ray muons. Students see how particle mass, charge, and energy determine track characteristics — thick and short for alphas, thin and erratic for betas, long and straight for muons.

Large rectangular diffusion cloud chamber with glass walls, black base plate, wooden trim, and hinged acrylic lid on a black stand

Figure 1: The diffusion cloud chamber apparatus. The black base plate sits on dry ice; alcohol-soaked felt in the lid creates the supersaturated vapor layer where particle tracks become visible.

Warning: Cryogenic Hazard

Danger: Radioactive Source Handling

Purpose

Safety Warnings

Warning: Cryogenic Hazard

Danger: Radioactive Source Handling

Purpose