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arXiv · 1810.00857

Measurement of the electron-antineutrino correlation in neutron beta decay: aCORN experiment

F. E. Wietfeldt·W. A. Byron·G. Darius·C. R. DeAngelis·M. T. Hassan·M. S. Dewey·M. P. Mendenhall·J. S. Nico·B. Collett·G. L. Jones·A. Komives·E. J. Stephenson
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Abstract

The aCORN experiment uses a novel asymmetry method to measure the electron-antineutrino correlation (a-coefficient) in free neutron decay that does not require precision proton spectroscopy. aCORN completed two physics runs at the NIST Center for Neutron Research. The first run on the NG-6 beam line in 2013--2014 obtained the result a = 0.1090 +/- 0.0030 (stat) +/- 0.0028 (sys), a total uncertainty of 3.8%. The second run on the new NG-C high flux beam line promises an improvement in precision to <2%.

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F. E. Wietfeldt, W. A. Byron, G. Darius, C. R. DeAngelis, M. T. Hassan, M. S. Dewey, M. P. Mendenhall, J. S. Nico, B. Collett, G. L. Jones, A. Komives, E. J. Stephenson. 2018-10-01. Measurement of the electron-antineutrino correlation in neutron beta decay: aCORN experiment. https://arxiv.org/abs/1810.00857

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