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Title: Final results for the neutron β -asymmetry parameter A 0 from the UCNA experiment
The UCNA experiment was designed to measure the neutron β-asymmetry parameter A 0 using polarized ultracold neutrons (UCN). UCN produced via downscattering in solid deuterium were polarized via transport through a 7 T magnetic field, and then directed to a 1 T solenoidal electron spectrometer, where the decay electrons were detected in electron detector packages located on the two ends of the spectrometer. A value for A 0 was then extracted from the asymmetry in the numbers of counts in the two detector packages. We summarize all of the results from the UCNA experiment, obtained during run periods in 2007, 2008–2009, 2010, and 2011–2013, which ultimately culminated in a 0.67% precision result for A 0 .
Authors:
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Award ID(s):
1812340
Publication Date:
NSF-PAR ID:
10160218
Journal Name:
EPJ Web of Conferences
Volume:
219
Page Range or eLocation-ID:
04004
ISSN:
2100-014X
Sponsoring Org:
National Science Foundation
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