"In a way I represent the third generation of Nobel laureates in physics."
Donald Glaser, on receiving his Nobel Prize
The story goes that Donald Glaser [b. 1926), a faculty member at the University of Michigan, was drinking a nice cold beer when he got the inspiration for what would eventually earn him the 1960 Nobel Prize in Physics. In 1952 he invented the very first bubble chamber, which was no bigger than a thumb. The idea was that subatomic particles, accelerated by a particle accelerator, could pass through a chamber containing a liquid. Under the right conditions a trail of tiny bubbles would be created as a particle passed through. By photographing and analyzing the bubbles, physicists could gain precious information about the nature of particles.
In 2006 Glaser denied that the bubbles in beer inspired him, though he did use beer as an early experimental liquid. Irrespective of how he got the idea, Glaser's concept worked, and bubble chambers sprang up all over the world to be used in atom smashers. The best and largest grew to sizes that could contain 706 cubic feet (20 cu m) of liquid hydrogen, stored just below its boiling point. As the particles enter the chamber, the internal pressure is reduced slightly using pistons, putting the liquid hydrogen into what can be described as a superheated metastable phase. This forces bubbles to form in the wake of the particles and, by decreasing the internal pressure further, these bubbles will expand until they are large enough to be imaged in 3-D by multiple cameras.
Bubble chambers dominated particle physics until the advent of wire-chamber detectors in the mid- 1980s. However, the bubble chamber is making a comeback as a tool to look for dark matter.
