Discovery of the Z particle, one of the carriers (gauge particles) of the weak nuclear force. This photographically coloured version of the original electronic image obtained from the UA1 detector at CERN, Geneva, on April 30, 1983, shows the tracks of an electron-positron pair (coloured purple) emerging back-to-back from the point where a proton and an antiproton collided at high energy in CERN's Super-Proton-Synchrotron (SPS) accelerator. The collision also produced a debris of other particles whose tracks are visible. The Z particle itself lives too briefly to be seen, but its existence is deduced from the tell-tale 'signature' of the electron-positron pair.

Photo website with Rights Managed and Royalty Free stock photos, images, illustrations and footage available for download immediately for commercial and editorial uses. Aflo is a leading independent supplier and producer of stock pictures and visual content. Search and find high quality images and video for design, print, web-use and publishing. Buy photos from our extensive collection of model released and property released sports images. Search some of the most beautiful travel and landscape pictures from our own photographers and license from our large collection of content, modern and archive, focusing on Japan. We provide free research. Register for personal account management and for full use of our Stock Photography website and start to download images now.