Results from the first year of experiments at KamLAND, an underground neutrino detector in central Japan, show that anti-neutrinos emanating from nearby nuclear reactors are “disappearing,” which indicates they have mass and can oscillate or change from one type to another.
Neutrinos are subatomic particles that interact so rarely with other matter that one could pass untouched through a wall of lead stretching from the earth to the moon. They’re produced during nuclear fusion, the reaction that lights the sun and other stars. Anti-neutrinos are created in fission reactions such as those that drive nuclear power plants.
Neutrino research at KamLAND is helping unlock secrets about the fundamental nature of matter, how the sun works, the composition and evolution of the Earth, the process of star collapse and the origin and future of the universe.
The University of Alabama has two faculty, a postdoctoral research associate and several graduate students who have been involved in the KamLAND project since the beginning of its construction in 1998.
“This research has put another piece of the puzzle in place,” said Dr. Jerry Busenitz, professor of physics. “KamLAND has provided an important confirmation that neutrinos do in fact oscillate.”
“There has been a wide range of hypotheses on this subject, and neutrino research is scientifically popular right now,” said Dr. Andreas Piepke, professor of physics. “The results of our research are strong evidence that we are well on the way to a full understanding of neutrinos.”
KamLAND stands for Kamioka Liquid-scintillator Anti-Neutrino Detector. Located in a mine cavern beneath the mountains of Japan’s main island of Honshu, near the city of Toyama, it is the largest low-energy anti-neutrino detector ever built. For more information go to uanews.ua.edu/dec02/neutrino120602.htm.