Charged particle tracks curving through a magnetic field, ionization trails glowing and decaying in a supercooled liquid medium.
ℹ Details ▾The bubble chamber was invented in 1952 by Donald Glaser, who won the 1960 Nobel Prize in Physics for the discovery. It works by holding a liquid — often liquid hydrogen — just above its boiling point in a superheated, depressurized state; as a charged particle passes through, it ionizes atoms along its path, and tiny vapor bubbles nucleate on those ions, tracing the particle's trajectory as a visible string of bubbles. A strong external magnetic field bends the paths of charged particles, and the direction and tightness of that curvature reveal the particle's momentum and the sign of its electric charge. Bubble chambers were central to mid-20th-century particle physics, enabling landmark discoveries such as the omega-minus baryon and the observation of neutral current interactions predicted by electroweak theory.