MesonsIn 1948, the University of California at Berkeley and the Atomic Energy Commission officially announced the artificial production of mesons using the 184-inch cyclotron at the university's Radiation Laboratory. Mesons in nature had previously been seen as cloud chamber tracks by Carl Anderson, and others (formed by cosmic rays) had been detected by other scientists in photographic plates made at high altitude. Now, at the limits of energy available from the cyclotron, these short-lived particles were generated artificially by Eugene Gardner and C.M.G. Lattes, using a beam of accelerated alpha particles fired at a thin carbon target. Time reported the discovery and hinted that the study of mesons might “lead in the direction of a vastly better source of atomic energy than the fission of uranium.”«[Image: Part of a photomicrograph of the track of one of the first mesons found by Gardener and Lattes, 1948. The meson enters from the bottom of this image. The star track shows a nuclear disintegration resulting from a colliding meson.] |