2002 Nobel Prize in Physics

Raymond Davis Jr. (University of Pennsylvania) and Masatoshi Koshiba (Univ. of Tokyo) shared half of this years Nobel prize in physics. Their citation reads "for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos".

Until we started to understand the nature of the nuclear forces, the origin of solar energy was a mystery. Because of the fundamental work in Nuclear Physics done by Hans Bethe, George Gamow, Willy Fowler, Ray Davis, M. Koshiba their many collaborators, we now know that Sun's energy originates from a series of nuclear reactions going on in its core. These nuclear reactions emit neutrinos which travel through the material in the Sun very easily. Solar models, developed by John Bahcall and others, predict the solar neutrino flux which reaches the Earth. ...more

The other half of the prize was won by Riccardo Giacconi (Associated Universities Inc.) "for pioneering contributions to astrophysics, which have led to the discovery of cosmic X-ray sources"

Artist's conception of a binary sytem. (NASA/HEASARC)

The Nobel Prize for Prof. Giacconi recognizes his enablement of the birth of X-ray astronnomy. This led to the discovery of neutron stars that accerete matter from a binary companion, releasing large amounts of gravitational energy. These objects periodically emit large flashes of X-rays as a result of nuclear reactions taking place in the built-up material. The exact details of what takes place awaits further illucidation of the nature of neutrons stars and the underlying nuclear physics. New nuclear physics facilities such as RIA will make a major contribution to this understanding. ...more

For more information:
Link to the Nobel Prize Committee web site
APS Media information for the 2002 Nobel Prize in Physics