Improved Measurement of Electron-antineutrino Disappearance at Daya Bay
- Creators
- Dwyer, D. A.
- Daya Bay Collaboration
Abstract
With 2.5× the previously reported exposure, the Daya Bay experiment has improved the measurement of the neutrino mixing parameter sin^2 2θ_(13) = 0.089 ± 0.010(stat) ± 0.005(syst). Reactor anti-neutrinos were produced by six 2.9 GW_(th) commercial power reactors, and measured by six 20-ton target-mass detectors of identical design. A total of 234,217 anti-neutrino candidates were detected in 127 days of exposure. An anti-neutrino rate of 0.944±0.007(stat)±0.003(syst) was measured by three detectors at a flux-weighted average distance of 1648 m from the reactors, relative to two detectors at 470 m and one detector at 576 m. Detector design and depth underground limited the background to 5 ± 0.3% (far detectors) and 2 ± 0.2% (near detectors) of the candidate signals. The improved precision confirms the initial measurement of reactor anti-neutrino disappearance, and continues to be the most precise measurement of θ_(13).
Additional Information
© 2013 Published by Elsevier B.V. The Daya Bay experiment is supported in part by the Ministry of Science and Technology of China, the United States Department of Energy, the Chinese Academy of Sciences, the National Natural Science Foundation of China, the Guangdong provincial government, the Shenzhen municipal government, the China Guangdong Nuclear Power Group, Shanghai Laboratory for Particle Physics and Cosmology, the Research Grants Council of the Hong Kong Special Administrative Region of China, University Development Fund of The University of Hong Kong, the MOE program for Research of Excellence at National Taiwan University, National Chiao-Tung University, and NSC fund support from Taiwan, the U.S. National Science Foundation, the Alfred P. Sloan Foundation, the Ministry of Education, Youth and Sports of the Czech Republic, the Czech Science Foundation, and the Joint Institute of Nuclear Research in Dubna, Russia. We thank Yellow River Engineering Consulting Co., Ltd. and China railway 15th Bureau Group Co., Ltd. for building the underground laboratory. We are grateful for the ongoing cooperation from the China Guangdong Nuclear Power Group and China Light & Power Company.Additional details
- Eprint ID
- 39857
- Resolver ID
- CaltechAUTHORS:20130812-084848347
- Ministry of Science and Technology of China
- Department of Energy (DOE)
- Chinese Academy of Sciences
- National Natural Science Foundation of China (NSFC)
- Guangdong Provincial Government
- Shenzhen Municipal Government
- China Guangdong Nuclear Power Group
- Shanghai Laboratory for Particle Physics and Cosmology
- Hong Kong Special Administrative Region of China
- University of Hong Kong University Development Fund
- National Taiwan University Research of Excellence MOE Program
- National Chiao-Tung University
- NSC
- NSF
- Alfred P. Sloan Foundation
- Czech Republic Ministry of Education Youth and Sports
- Czech Science Foundation
- Joint Institute of Nuclear Research
- Created
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2013-08-12Created from EPrint's datestamp field
- Updated
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2021-11-09Created from EPrint's last_modified field