The Bubble Chamber Technique for Photographing Interactions of High-Energy Particles

The alternating gradient synchroton (AGS) supplies high-energy particles that are beamed on a target. The particles of interest are focused and steered by magnets through the visible volume of the bubble chamber. Chambers are usually filled with liquid hydrogen, which serves as a target for the incoming particles. To make a chamber sensitive to radiation, a piston is quickly raised, reducing the chamber pressure below the vapor pressure of the liquid, and thus superheating the liquid hydrogen. If, during this time, particles from the accelerator are passed through the chamber, the resulting interactions will nucleate boiling and leave bubble tracks along their paths. After a time delay which enables the bubbles to grow to the proper size, a xenon strobe tube is flashed, and the tracks are photographed. Tracks appear in the chamber as dark spots on a bright background. To increase picture production, chambers are operated in a multipulse mode. A Wilkins-type camera and fast data box enable advancing and tagging a single frame of film, on demand, in less than 100 ms. The fast advance is effected when a blast of air pushes the film into a cup-shaped transfer pocket. Typically, 6 in of 70mm film is advanced in 30 ms.

Print ISSN

0361-4573

Published

1970-03

Content type

Original Research

DOI

10.5594/J13613