Historical Content Note: The following material is reprinted from publications from throughout Fermilab's history. It should be read in its original historical context.

Discovery of the Bottom Quark, Upsilon

In the summer of 1977, a team of physicists, led by Leon M. Lederman, working on experiment 288 in the proton center beam line of the Fermilab fixed target areas discovered the Upsilon. This discovery was eventually understood as being the bound state of the bottom quark and its antiquark. Their data was confirmed in experiments conducted in 1978 at Fermilab, the CERN ISR in Geneva, Switzerland and DORIS at DESY in Hamburg, Germany.

Complete records of the discovery can be found in the Fermilab archives, and for additional reading, please see the special summer edition of the 1977 Village Crier about the Upsilon discovery and Daniel M. Kaplan's Illinois Institute of Technology preprint, "The discovery of the Upsilon Family," IIT-HEP-94/1, November 1994. More technical reports are available in "Observation of a Dimuon Resonance at 9.5 GeV in 400 GeV Proton-Nucleus Collisions," Physical Review Letters 39, p. 252, (1977) and Leon M. Lederman, "The Upsilon Particle," Scientific American, October 1978, vol. 239, no. 4, pp. 72-80.