Word: gamma
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Better Chemists. Weiss and Shipman dried the clam flesh, reduced it to ash and dissolved the ash in dilute acid. The solution showed characteristic gamma rays that could come only from cobalt 60. This was odd, they thought; cobalt 60 is not a fission product, and it had not been found in other radioactive material, even in samples from much closer to Ground Zero. To make doubly sure. Weiss and Shipman ran a careful analysis. One clam proved to contain one-tenth of a microcurie of cobalt 60; the other had one-third of a microcurie...
...year Marquette started an "optional class privilege" (i.e., unlimited cuts) program for top students, and this year Williams began putting its better boys in special small seminars, now lets them carry out research projects to wherever those projects might lead (sample subject: annihilation of positrons and electrons to produce gamma rays). At college after college, the cry seems to be: set the student free. Examples: ¶ Now ten years old, Yale's Scholars of the House program has provided much of the inspiration for the big fight for independence. Each year 15 to 18 seniors are allowed to pick...
...this action was predicted by theory. The Berkeley scientists, by carefully screening out of the beam all antiprotons and gamma rays, proved that it actually happens. The surviving mesons, neutrons and anti-neutrons were allowed to pass into a counting device which measures flashes of energy released by each entering particle. The ordinary neutrons gave small flashes. The mesons gave flashes about twice as strong. Occasional flashes 20 times as strong (2 billion volts) could be only the result of the mutual annihilation of a neutron and an antineutron...
Radiation Resistance. While working on the heat-resistant components, G.E. scientists found that materials unaffected by heat can often stand atomic radiation, too. So they finally came up with a set of gadgets that ignores neutrons and gamma rays. Two of their assemblies, enclosed in a heated capsule at 842° F., spent 1,000 hours in the heart of the Oak Ridge nuclear reactor. They worked all the time, affected neither by the heat nor by the storm of radiation...
Pair of Creation. In 1932, physicists discovered that positive electrons (positrons) are created out of energy by cosmic rays. They can also be made artificially by high-energy gamma rays from radioactive elements. Positrons do not last long; as soon as one of them hits a normal electron, both particles are annihilated, turning back into the energy out of which they were made. But the proof that positrons exist was a victory for believers in nature's symmetry. Better still was the fact when a positron is created, it always appears in a "pair" with an ordinary negative electron...