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arXiv · 1104.2778

A New Limit on Time-Reversal Violation in Beta Decay

H. P. Mumm·T. E. Chupp·R. L. Cooper·K. P. Coulter·S. J. Freedman·B. K. Fujikawa·A. Garcia·G. L. Jones·J. S. Nico·A. K. Thompson·C. A. Trull·J. F. Wilkerson·F. E. Wietfeldt
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Abstract

We report the results of an improved determination of the triple correlation $D P \cdot(p_{e}\times p_ν)$ that can be used to limit possible time-reversal invariance in the beta decay of polarized neutrons and constrain extensions to the Standard Model. Our result is $D=(-0.96\pm 1.89 (stat)\pm 1.01 (sys))\times 10^{-4}$. The corresponding phase between g_A and g_V is $ϕ_{AV} = 180.013^\circ\pm0.028^\circ$ (68 % confidence level). This result represents the most sensitive measurement of D in beta decay.

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H. P. Mumm, T. E. Chupp, R. L. Cooper, K. P. Coulter, S. J. Freedman, B. K. Fujikawa, A. Garcia, G. L. Jones, J. S. Nico, A. K. Thompson, C. A. Trull, J. F. Wilkerson, F. E. Wietfeldt. 2011-04-26. A New Limit on Time-Reversal Violation in Beta Decay. https://doi.org/10.1103/physrevlett.107.102301

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