Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published September 11, 2015 | Supplemental Material + Published + Submitted
Journal Article Open

New Measurement of Antineutrino Oscillation with the Full Detector Configuration at Daya Bay


We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×10^5 GW_(th) ton  days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six ^(241)Am−^(13)C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin 2^2θ_(13) and |Δm^2_(ee)| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave sin^2 2θ_(13)=0.084±0.005 and |Δm^2_(ee)|=(2.42±0.11)×10^(−3) eV^2 in the three-neutrino framework.

Additional Information

© 2015 American Physical Society. Received 13 May 2015; published 11 September 2015. Daya Bay is supported in part by the Ministry of Science and Technology of China, the U.S. Department of Energy, the Chinese Academy of Sciences, the CAS Center for Excellence in Particle Physics, the National Natural Science Foundation of China, the Guangdong provincial government, the Shenzhen municipal government, the China General Nuclear Power Group, Key Laboratory of Particle and Radiation Imaging (Tsinghua University), the Ministry of Education, Key Laboratory of Particle Physics and Particle Irradiation (Shandong University), the Ministry of Education, Shanghai Laboratory for Particle Physics and Cosmology, the Research Grants Council of the Hong Kong Special Administrative Region of China, the 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 Joint Institute of Nuclear Research in Dubna, Russia, the NSFC-RFBR joint research program, the National Commission of Scientific and Technological Research of Chile, and the Tsinghua University Initiative Scientific Research Program. We acknowledge 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 General Nuclear Power Group and China Light and Power Company.

Attached Files

Published - PhysRevLett.115.111802.pdf

Submitted - 1505.03456v2.pdf

Supplemental Material - chi2_scan.dat

Supplemental Material - supplemental_dm2ee.pdf


Files (1.4 MB)
Name Size Download all
550.6 kB Preview Download
393.3 kB Preview Download
187.6 kB Download
230.6 kB Preview Download

Additional details

August 20, 2023
October 24, 2023