View of part of the tunnel of the PETRA electron/positron accelerator ring at the DESY particle physics lab, Hamburg. PETRA is km in circumference

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View of part of the tunnel of the PETRA electron/positron accelerator ring at the DESY particle physics lab, Hamburg. PETRA is km in circumference & accelerates electrons & positrons in opposite directions in the same beam pipe up to energies of about 23 GeV per beam. There are 4 interaction regions where the electrons & positrons collide & experiments detect the results. PETRA was completed in 1978. The photograph shows several of the long, red, dipole magnets that bend the particles round the ring, and one of the square focusing magnets. Also a DESY bicycle for the long trip round the tunnel! Photographed May 1984.

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Size: 5150px × 3461px
Photo credit: © DAVID PARKER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: accelerator, desy, german, germany, hamburg, laboratory, magnet, nuclear, particle, petra, physics, research