Final results for the neutron $\beta$-asymmetry parameter $A_0$ from the UCNA experiment

Abstract

The UCNA experiment was designed to measure the neutron $\beta$-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 $A_0$.

arXiv comment6 pages, 7 figures, to appear in proceedings of the International Workshop on Particle Physics at Neutron Sources 2018

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Cited by in corpus (2)

• Improved limits on Fierz Interference using asymmetry measurements from the UCNA experiment
• Opportunities and open questions in modern $\beta$ decay