How does a spark chamber detect particles?

A spark chamber detects particles by ionizing gas molecules, creating a visible spark along the particle's path.

When a charged particle passes through a gas-filled spark chamber, it ionizes the gas molecules along its path. This ionization creates a trail of charged particles, which can be detected as a visible spark. The spark chamber consists of a gas-filled chamber with two parallel metal plates, one of which is connected to a high voltage source. When a charged particle passes through the chamber, it ionizes the gas molecules, creating a trail of charged particles that are attracted to the high voltage plate. As these charged particles move towards the plate, they collide with other gas molecules, creating more ionization and a visible spark.

Spark chambers are commonly used in particle physics experiments to detect and track the paths of charged particles. By analyzing the patterns of sparks in a spark chamber, physicists can determine the charge, momentum, and energy of the particles that passed through the chamber. Spark chambers have been largely replaced by more advanced particle detectors, such as drift chambers and time projection chambers, but they remain an important tool in particle physics research.