On July 31, scientists attending the International Conference on High Energy Physics in Osaka, Japan, will present the first results of two experiments aimed at elucidating why the Universe contains far more matter than antimatter. The experiments were conducted by more than 500 physicists from nine countries in the BABAR collaboration, working on the Asymmetric B Factory at the U. S. Department of Energy`s Stanford Linear Accelerator Center (SLAC) in California, and by about 300 scientists in the international Belle collaboration working on the KEKB collider in Japan.
Research leaders will discuss the performance of the two particle colliders and show early results of these experiments at 10:45 a.m. at the International House, Osaka, 3rd Floor, Room 5. Addressing the press will be Hirotaka Sugawara, director of the Japanese National Laboratory for High Energy Physics (KEK), Jonathan Dorfan, director of SLAC, Fumihiko Takasaki of KEK and Steven Olsen of the University of Hawaii, co-spokesmen of the Belle collaboration, David Hitlin of the California Institute of Technology, spokesman of the BABAR collaboration, and Gerard Bonneaud of the Ecole Polytechnique in Paris, deputy spokesman of BABAR.
Designed and built by SLAC and the Lawrence Berkeley and Lawrence Livermore National Laboratories with $177 million in funding from the U.S. Department of Energy, the B Factory`s innovative electron-positron collider creates millions of short-lived subatomic particles known as B mesons. Their behavior provides clues that will help scientists from Canada, China, France, Germany, Great Britain, Italy, Norway, Russia and all across the United States search for subtle differences between matter and antimatter.
SLAC`s B Factory has exceeded expectations and continues to do so, having nearly reached design performance after only a year of operations. Normally a new particle collider with such innovative features must undergo a long tuning period, often taking several years before it performs at its full potential. The 1,200-ton particle detector surrounding the collision point, called BABAR, is a similarly complex device that must be carefully adjusted.
``But the entire B Factory, both collider and detector, has come on line smoothly and in record time, to the great credit of the machine builders and the delight of the hundreds of BABAR scientists now trying to cope with the flood of data,`` says SLAC Director Dorfan.
Until the week preceding the Osaka conference, the more than 500 physicists involved in the BABAR collaboration did not even know a key result of their ongoing experiment, which will continue running through October. They measure an asymmetry parameter that reflects an anticipated difference between matter and antimatter. Analysis of the data was unusual because it was ``blinded`` by insertion of a ``fudge factor`` so that researcher bias would not influence the answer.
These and other preliminary results of the BABAR experiment will be unveiled in Osaka, as will those of the Belle experiment. Physicists are eagerly waiting to see how these results compare with one another and with earlier measurements from Cornell and Fermilab.
Contact: Michael Riordan, SLAC (650) 926-2601;
e-mail: michael@slac.stanford.edu
Editors Note: A backgrounder on B Factory science is available
on the Web at http://www.stanford.edu/dept/news/report/news/august9/bfactorybk-89.html.
Photos and illustrations of the B Factory are available for download at:
http://www.slac.stanford.edu/slac/media-info/pressphoto_bfactory.html.