Word: neutron
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Invisible Springs. Compared with the difficulties of controlling fusion, producing energy from nuclear fission is relatively simple. In fission-which occurs in A-bomb explosions and powers today's nuclear plants-a speeding neutron is used to split the atomic nucleus of a heavy element like uranium into the nuclei of one or more lighter elements. In the process, more neutrons are given off. But the mass of the resulting nuclei and neutrons is somewhat less than the mass of the original nucleus; the missing matter-as predicted by the famed Einstein equation E=mc2-has been converted into...
...carriers of mass can be further divided into leptons, which do not feel the "strong" force, and hadrons, which do. There are four leptons: the electron, the muon, the electron neutrino and the muon neutrino. There are hundreds of hadrons. The neutron and proton are both hadrons and so are subject to the paull of the "strong" force...
...very massive star may have an even stranger fate. Driven by its own immense gravitation, it collapses through its neutron star stage, crushing its matter into a volume so small that it virtually ceases to exist. The gravity of its tiny remnant is so great that nothing, not even light, can escape from it. All external evidence of its presence disappears, and the star, like the Cheshire cat, vanishes, leaving behind only the grin of its disembodied gravity. Anything that fell into such a "black hole" would quite literally be crushed out of existence...
...While neutron stars and black holes can result from the death of massive stars, the explosions that precede them create elements essential to the birth of new stars and spread through the universe the materials essential to life. "Stars have two purposes," says Stanford University Astrophysicist Robert Wagoner. "They give energy in the form of light, and they produce the heavy elements that we are made...
Initial Results. The director of Fermilab's neutron irradiation program, Dr. Lionel Cohen of Chicago's Michael Reese Hospital, is encouraged by the initial results, but emphasizes that the use of the Fermilab accelerator for treating cancer is still highly experimental. No one can tell what, if any, long-term damage may result from the use of high-energy neutrons. Furthermore, neutron treatment is suitable for only a small fraction of cancer patients. Says Cohen: "Only 15% of patients now being treated with conventional radiation could benefit from neutron therapy. There has to be a localized cancer...