Malcolm Browne writes today on sonoluminescence to produce cold fusion. Nix crypto, no excuso. For email copy send blank message with subject: SON_fuz Some tidbits: New Shot at Cold Fusion By Pumping Sound Waves Into Tiny Bubbles [Drawing caption] New Fusion Recipe: Sound Plus Bubbles Fusion creates great energy but requires tremendous temperatures. In a new approach that scientists hope might reach such temperatures, they are using minuscule bubbles as the focus for sound waves. In this figure, a tiny heating element boils just enough water to create a single micron-sized bubble. A sound field makes the bubble pulsate. As it expands, it absorbs sound energy. Then it violently collapses, launching a spherical, inward-moving supersonic shock wave, which produces enormous temperatures and a flash of light. By Malcolm W. Browne Ever since the first hydrogen bomb was detonated in 1952, scientists have sought to harness thermonuclear fusion as a peaceful power source, but that goal has proved tantalizingly elusive. Now, however, there seems to be an outside chance that a wholly new technique could achieve it. Bombarding microscopic bubbles with intense sound waves could convert the bubbles into minuscule fusion furnaces. Recent experiments by a half-dozen laboratories suggest that a mysterious phenomenon called sonoluminescence may be capable of raising the temperature of gas trapped in a tiny bubble to 1.8 million degrees Fahrenheit or more -- enough, in principle, to ignite fusion. If fusion were achieved, a microbubble could be expected to radiate neutrons, nuclear particles produced by thermonuclear reactions. So far, the laboratories experimenting with sonoluminescence have failed to detected any neutrons, but there are other signs that the project is far from hopeless. *** Lawrence Livermore Laboratory in California, the nation's preeminent hydrogen bomb laboratory, has conducted some small experiments on "sonofusion," the name that would be bestowed on any fusion technique powered by sonoluminescent bubbles. As part of its nuclear weapons research programs during the 1980's, Livermore built the Nova laser, which focuses multiple beams of ultrapowerful lasers from all directions on a small target. Among the targets Livermore has tested are tiny, hollow glass spheres filled with hydrogen isotopes. In a typical experiment, the laser beams are turned on, the glass instantly vaporizes and the resulting shock wave of glass vapor is driven inward to compress the hydrogen. The idea is to get the hydrogen hot enough to initiate fusion. *** Still, the nation's thermonuclear bomb designers eventually solved similar problems for full-scale hydrogen bombs, and Livermore's scientists believe that inertial confinement fusion as a means of generating comparatively cheap electric power will eventually prove to be practical. The tiny bubbles used in sonoluminescence experiments are similar in terms of their fusion physics to their big brothers, hydrogen bombs and on a smaller scale, to the glass spheres used in inertial confinement fusion. ------------------- End tids Note: The NYT advertises an email address for "comments from readers about published articles and suggested areas of coverage": <scitimes@nytimes.com>