John C. van der Velde, professor of physics, retired from active faculty status on May 31, 1995.

Professor van der Velde received his AB. degree from Hope College in 1952 and his M.A and Ph.D. degrees from the University of Michigan in 1953 and 1958, respectively. He joined the faculty as an instructor of physics in 1958 and was promoted to assistant professor in 1961, associate professor in 1964, and professor in 1968.

With various of his colleagues, Professor van der Velde conducted important research on muonelectron universality in K decays using the liquid xenon bubble chamber and important studies of proton-deuteron and pi-proton, pi-deuteron interactions. Beginning in 1960, he and his colleagues worked on the design and construction of the 40-inch freon bubble chamber, which had a productive lifetime at the Argonne ZGS. Following completion of the Fermilab accelerator and the 15-foot hydrogen bubble chamber, Professor van der Velde joined the larger collaboration working with this chamber in studying high-energy neutrinoproton and anti-neutrino nucleon interactions.

In the 1980s, Professor van der Velde joined with colleagues to form the IMB collaboration, building a 10,000 cubic meter water Cherenkov detector in a salt mine to search for proton decay. No candidates for proton decay were seen-a significant result, and the experiment established important lower limits to the proton lifetime. In February 1987, the IMB detector observed signals from the interaction of the 1987A Supernova and, in 1989, Professor van der Velde was a co-winner of the Rossi Prize from the American Astronomical Society. One of the outstanding astrophysical observations of recent years, the detection of neutrinos was the first observation of anything other than electromagnetic radiation from a source outside the solar system and gave the first experimental confirmation of the theory of supernova production and stellar collapse. Recently, Professor van der Velde has been collaborating on cosmic ray studies with the CASA-MIA Extensive Air Shower Array in Utah. An objective of this cosmic ray program is to seek evidence for point sources of cosmic rays, presumably from energetic primary gamma rays.

The Regents now salute this distinguished professor by naming John C. van der Velde professor emeritus of physics.