H1 particle detector. Technician working on the H1 detector of the HERA accelerator at DESY (Deutsche Elektronen Synchrotron). HERA (Hadron Electron Accelerator Ring) consists of a pair of accelerator rings mounted in a 6.3km circumference tunnel. The H1 detector is placed at one crossing point of the rings. In the centre of the detector, protons from one ring will collide with electrons from the other ring at a combined energy of 850 GeV. It is hoped that data from this detector will provide more information about the quarks in protons and the gluon force moderators that bind them together. Photographed near Hamburg, Germany, in May 1999.