Word: decays
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Dates: during 1960-1969
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Near the beginning of time, the universe almost certainly contained many elements heavier than uranium, the heaviest element that exists naturally on earth. Gradually these "transuranium" elements disappeared, decomposing by radioactive decay into lighter and more stable elements. During the past few decades, however, at least eleven transuranium elements and their isotopes have reappeared, thanks to the ingenuity of man. In their latest atomic synthesis, nuclear physicists have produced the heaviest atom known to man, a new isotope of the element mendelevium, which itself was first artificially created...
...laboratory's heavy ion linear accelerator to bombard a tiny amount of einsteinium (a transuranium element discovered in 1952) with alpha particles which consist of two protons and two neutrons. "We expected the alpha particles to join with the heavier isotope of einsteinium," says Hulet, "and then decay by a process called 'electron capture' to fermium...
...mysterious and heavy isotope, which they later identified as mendelevium 258. Even stranger, the isotope-unlike many of its transuranium counterparts -appeared to be in no rush to disappear. The California scientists eventually determined that its half life (the time in which half the atoms of an element decay) was nearly two months. This compared, for example, with only eight seconds for lawrencium 257, until now the heaviest of the known atoms...
...understands why mendelevium 258 is so long-lived. "It's possible," speculates Hulet, "that because of the structure of the nucleus, certain kinds of decay are hindered." Whatever the reason, scientists are delighted. The long half life will enable them eventually to accumulate more substantial amounts of the new isotope and to study its properties at leisure. Even more important, mendelevium stays around long enough to make a good target for high-velocity particle accelerators. And it is by the bombardment of uranium and transuranium elements that even heavier elements and their isotopes have been created...
...orgy is expected to be brief, but the consequences of last week's decision will not be. Doctors and dentists are already complaining that cheaper candy will broaden waistlines and decay teeth. Beyond that, lower supermarket prices will probably mean an end to many of the 60,000 little neighborhood shops, which include sweets among their sundries, and last year accounted for 48% of Britain's candy sales. Most important, the candy case is the first in a series on the docket of the Restrictive Practices Court. The court is now scheduled to rule on price fixing...