Antiproton Research Resumes at CERN

Experiments designed to probe differences between matter and antimatter using low‐energy antiprotons have been on hold since CERN shut down its Low‐Energy Antiproton Ring (LEAR) in December 1996. But the progress made at LEAR motivated the construction at CERN of a $5 million new facility, the Antiproton Decelerator (AD) (see PHYSICS TODAY, March 1996, page 17; November 1996, page 9; and May 1997, page 19). The photo shows the dipole (red) and quadrupole (blue) magnets in a section of the new ring. Antiprotons enter from the transfer line on the right.