Propane Bubble Chambers at the Joint Institute for Nuclear Research (1964)

Bubble chambers are typically used to record interactions between high-energy particles and the nuclei of the chamber’s working fluid, or to observe particle decays. In the former case, the working fluid also serves as the detection medium. When an ionizing particle enters the chamber, its trajectory is marked by a trail of vapor bubbles, which can then be photographed. The ability to visually analyze these events made it possible to discover particles that could not be detected by any other means. Most notably, this includes the cascade decays of strange particles, whose decay products were either fully or partially captured in the chamber images.