Studies nuclear fusion and the sun: How long will it shine?
Chemist Richard L. Hahn of Moriches, N.Y., will be honored on March 28 by the world's largest scientific society for his work with solar neutrinos, high-speed particles from which researchers learn about the sun and nuclear fusion. He will receive the American Chemical Society Award for Nuclear Chemistry at the Society's national meeting in San Francisco.
"I study the sun to figure out how it works and how long it may shine," said Hahn, a nuclear chemist at Brookhaven National Laboratory. "But the light and heat we're receiving now came from reactions that took place in the core of the sun many thousands of years ago. The only way we have of knowing what it's doing now is to look at neutrinos."
Unlike most products of solar fusion, newly formed neutrinos rapidly escape the sun. They hardly interact with atoms, zipping through solid matter as if it were empty space. This makes them difficult to detect - they pass through our atmosphere, the Earth, even our bodies without leaving a trace.
On rare occasions, a single neutrino collides with a single atom's nucleus. Hahn and his research team have devised ways to detect and count these events.
One tool is a giant tank, buried under Italy's Apennine Mountains and filled with 30 tons of gallium. Each month, neutrino collisions cause 5 to 15 atoms of germanium to appear among the tank's 260,000 trillion trillion (2.6 followed by twenty-nine zeros) gallium atoms. Hahn separates and collects the germanium.
Data from the tank and other detectors appear to support the hypothesis that neutrinos are not without mass. If true, the discovery would overturn the neutrino's very definition, force re-evaluation of fundamental theories, and perhaps even help solve the missing-matter problem in the universe.
Hahn was interested in math, chemistry and physics even as a child, he said. Traveling one day in the New York subway, he noticed the headline of a man's newspaper. "It announced the United States had dropped an atomic bomb on Japan," he said. "I remember thinking, 'I'm going to have to find out about that.'"
The ACS Award for Nuclear Chemistry is sponsored by The Gordon and Breach Publishing Group of Newark, N.J.
A nonprofit organization with a membership of 161,000 chemists and chemical engineers, the American Chemical Society (www.acs.org) publishes scientific journals and databases, convenes major research conferences, and provides educational, science policy and career programs in chemistry. Its main offices are in Washington, D.C., and Columbus, Ohio.