Word: meson
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Dates: during 1940-1949
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...University of California admitted last week (after too many garbled rumors in the press) that it had created the first man-made meson. U.C. did it with its 4,000-ton cyclotron. The news caused a sizable flurry throughout the world of physics-for mesons are closely connected with the unknown force that holds matter together...
...Mesons are mysterious, short-lived particles knocked out of .atomic nuclei. It takes a lot of punch to knock them out. Before the 4,000-ton cyclotron developed sufficient punch, the only mesons in captivity had been trapped in the wild. Dr. Carl Anderson of CalTech found their characteristic tracks in a cloud chamber. Other scientists found two types, heavy and light, in photographic plates exposed on high mountains. All had been formed by cosmic rays, the enormously powerful particles that strike down out of space. No man-pushed particle was strong enough to engender a single meson...
...Berkeley is just barely strong enough. Dr. Eugene Gardner, 35, and Brazilian-born Dr. C.M.G. Lattes, 23, put a thin carbon target in a beam of alpha particles (helium nuclei) in the cyclotron chamber. Figuring that the alpha particles had enough power (380 million electron volts) to knock mesons out of the carbon atoms, Gardner & Lattes put a stack of special photographic plates at the spot where the mesons should hit. Then they turned on the cyclotron. When they developed the plates, they found the characteristic wavy tracks of negative mesons. Some of them ended in "stars," the atomic...
...other extreme of physics-the infinitesimally small end-there was also baffling news. Last week, Dr. J. Robert Oppenheimer, ex-head of the Los Alamos (atom bomb) Laboratory, postulated a new sub-atomic particle: the neutral meson, which leads an even more feverishly active life than the positive and negative meson which scientists already know about. In its normal habitat within an atomic nucleus, it "lives" only one hundredth of a sextillionth (1/100,000,000,000,000,000,000,000th) of a second. The neutral meson's brief life, remarked Professor Oppenheimer, may be the reason no physicist...
When a negative meson hit a nucleus, they theorized, its mass turned into energy. The added energy made the nucleus break into smaller particles, which flew apart and traced the chicken-track lines...