The Daya Bay Reactor Neutrino Experiment, which will include researchers from Rensselaer Polytechnic Institute, has begun its quest to answer some of the most puzzling questions about the elusive elementary particles known as neutrinos. The first completed set of twin detectors for the experiment is now recording interactions of antineutrinos (antipartners of neutrinos) as they travel away from the powerful reactors of the China Guangdong Nuclear Power Group in southern China.

Neutrinos are uncharged particles produced in nuclear reactions, such as in the sun, by cosmic rays, and in nuclear power plants. They come in three types or “flavors” — electron, muon, and tau neutrinos — that morph, or oscillate, from one form to another, interacting hardly at all as they travel through space and matter, including people, buildings, and planets like Earth.

The start-up of the Daya Bay experiment marks the first step in the international effort of the Daya Bay Collaboration to measure a crucial quantity related to the third type of oscillation, in which the electron-flavored neutrinos morph into the other two flavored neutrinos.

Rensselaer researchers, led by Professor of Physics, Applied Physics and Astronomy James Napolitano, will be involved in the design, procurement, installation, and operation of the water purification system that feeds all three experimental halls involved in the project.

“Knowledge of the neutrino mixing angle will help all of us understand the origin of matter in the universe,” Napolitano said.

“This is a remarkable achievement after eight years of effort — four years of planning and four years of construction – by hundreds of physicists and engineers from around the globe,” says Yifang Wang of the Institute of High Energy Physics (IHEP) of the Chinese Academy of Sciences, co-spokesperson for the Daya Bay Collaboration. “We worked collectively to build the underground experimental facility to detect antineutrinos from reactors, in order to find a new type of neutrino oscillation and measure it quantitatively.” 

“The first data from Daya Bay sets us on a path that will lead to measurement of the amplitude of the oscillation due to the least-known mixing angle to within 1 percent,” says Daya Bay co-spokesperson Kam-Biu Luk, of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley. “That precision is an order of magnitude better than present measurements and much more precise than other experiments now in progress. The results will be a major contribution to understanding the role of neutrinos in the evolution of basic kinds of matter in the earliest moments after the big bang, and why there is more matter than antimatter in the universe today.”   

China and the United States lead the Daya Bay Reactor Neutrino Experiment, which includes participants from Russia, the Czech Republic, Hong Kong, and Taiwan. The Chinese effort is led by project manager Yifang Wang of the Institute of High Energy Physics, and the U.S. effort is led by project manager Bill Edwards of Lawrence Berkeley National Laboratory and chief scientist Steve Kettell of Brookhaven National Laboratory.

The full news release on this project can be found at http://dayawane.ihep.ac.cn/docs/DYB_data_taking_20110815.html

The collaborating institutions of the Daya Bay Reactor Neutrino Experiment are Beijing Normal University, Brookhaven National Laboratory, California Institute of Technology, Charles University, Chengdu University of Technology, China Guangdong Nuclear Power Group, China Institute of Atomic Energy, Chinese University of Hong Kong, Dongguan University of Technology, Joint Institute for Nuclear Research, University of Hong Kong, Institute of High Energy Physics, Illinois Institute of Technology, Iowa State University, Kurchatov Institute, Lawrence Berkeley National Laboratory, Nanjing University, Nankai University, National Chiao-Tung University, National Taiwan University, National United University, North China Electric Power University, Princeton University, Rensselaer Polytechnic Institute, Shandong University, Shanghai Jiao Tong University, Shenzhen University, Siena College, Tsinghua University, University of California at Berkeley, University of California at Los Angeles, University of Cincinnati, University of Houston, University of Illinois at Urbana-Champaign, University of Science and Technology of China, Virginia Polytechnic Institute and State University Blacksburg, University of Wisconsin, Madison, College of William and Mary, and Sun Yat-Sen (Zhongshan) University.

For more information, visit http://dayawane.ihep.ac.cn/twiki/bin/view/Public/WebHome

Contact information

Gabrielle DeMarco, Rensselaer Polytechnic Institute, 518-276-6542, demarg@rpi.edu

Yifang Wang, co-spokesperson, IHEP, +86-10-88236076, yfwang@ihep.ac.cn

Kam-Biu Luk, co-spokesperson, Berkeley Lab and UC Berkeley, +1-510-486-7054, +1-510-642-8162, k_luk@lbl.gov

Tongzhou Xu, IHEP Public Affairs, +86-10-88236421, xutz@ihep.ac.cn

Kendra Snyder, Brookhaven Public Affairs, +1-631-344-8191, ksnyder@bnl.gov

Lynn Yarris, Berkeley Lab Public Affairs, +1-510-486-5375, lcyarris@lbl.gov