DAVID PARKER / SCIENCE PHOTO LIBRARY DAVID PARKER / SCIENCE PHOTO LIBRARY
Drift chamber. Assembly of a large drift chamber for a detector at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). Drift chambers are used to detect particle momentum and position. Each chamber is filled with a mixture of argon and ethane gas. As a particle traverses the gas, it creates a trail of ionised gas. Electrons liberated by ionisation move toward some of the chamber's 2000 sense wires. Each electron creates its own electric field, ionising more gas and liberating more electrons in an 'avalanche effect'. The result is a burst of electrons which may be detected and measured by computers. Jefferson Lab is at Newport News, Virginia, USA.
Model release not available. Property release not required.