Word: positrons
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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...
...theory of neutrinos predicts that when one hits a proton (an infrequent event), a positron (positive electron) is emitted, and the proton turns into a neutron. Both new particles are unstable. The positron hits an electron, and both are "annihilated," turning into gamma rays. The neutron is absorbed by almost any kind of matter, and if a little cadmium is around, the neutrons captured by it give another burst of energy...
...when the reactor was in operation, the detecting instruments registered "an event"-two flashes of light of exactly correct intensity and timing. This meant that a single neutrino (out of many billions per second) had hit a proton (out of billions along its path) and turned it into a positron and a neutron. After watching this happen for a total of 1,371 hours and taking elaborate precautions to eliminate false signals, Reines and Cowan announced that they had really detected neutrinos. AEC Commissioner Willard F. Libby congratulated them on their "magnificent accomplishment." Now nuclear physics can use neutrinos without...
Anti-Matter. As a result of the new discovery, it is now theoretically possible to create anti-hydrogen. The atoms of ordinary hydrogen have a proton in their centers with a negative electron revolving around it. Anti-hydrogen would have an antiproton and a positron (positive electron). Both these "anti" particles are now available, but since anti-hydrogen cannot live in peace with ordinary matter, it will be hard to create and even harder to preserve for more than a few millionths of a second...
...have explored the crust and core of the earth, and found out as much as any men alive about the nature of seismic waves, earthquakes, aftershock. Physicist C.C. Lauritsen produced the first 1,000,000-volt X-ray tube, and Carl Anderson won a Nobel Prize for discovering the positron. Meanwhile, Caltech biologists have been probing their own areas of the invisible. Geneticist Alfred H. Sturtevant described the linear order of genes; Calvin B. Bridges provided proof for the chromosome theory of heredity. In determining that genes control the synthesis of vitamins and amino acids, George Beadle discovered the bread...