Precision Measurement of the Neutron Beta-Decay Asymmetry

M. P. Mendenhall; R. W. Pattie Jr; Y. Bagdasarova; D. B. Berguno; L. J. Broussard; R. Carr; S. Currie; X. Ding; B. W. Filippone; A. García; P. Geltenbort; K. P. Hickerson; J. Hoagland; A. T. Holley; R. Hong; T. M. Ito; A. Knecht; C. -Y. Liu; J. L. Liu; M. Makela; R. R. Mammei; J. W. Martin; D. Melconian; S. D. Moore; C. L. Morris; A. Pérez Galván; R. Picker; M. L. Pitt; B. Plaster; J. C. Ramsey; R. Rios; A. Saunders; S. J. Seestrom; E. I. Sharapov; W. E. Sondheim; E. Tatar; R. B. Vogelaar; B. VornDick; C. Wrede; A. R. Young; B. A. Zeck

doi:10.1103/physrevc.87.032501

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arXiv · 1210.7048

Precision Measurement of the Neutron Beta-Decay Asymmetry

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Abstract

A new measurement of the neutron $\beta$-decay asymmetry $A_0$ has been carried out by the UCNA collaboration using polarized ultracold neutrons (UCN) from the solid deuterium UCN source at the Los Alamos Neutron Science Center (LANSCE). Improvements in the experiment have led to reductions in both statistical and systematic uncertainties leading to $A_0 = -0.11954(55)_{\rm stat.}(98)_{\rm syst.}$, corresponding to the ratio of axial-vector to vector coupling $\lambda \equiv g_A/g_V = -1.2756(30)$.

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M. P. Mendenhall, R. W. Pattie Jr, Y. Bagdasarova, D. B. Berguno, L. J. Broussard, R. Carr, S. Currie, X. Ding, B. W. Filippone, A. García, P. Geltenbort, K. P. Hickerson, J. Hoagland, A. T. Holley, R. Hong, T. M. Ito, A. Knecht, C. -Y. Liu, J. L. Liu, M. Makela, R. R. Mammei, J. W. Martin, D. Melconian, S. D. Moore, C. L. Morris, A. Pérez Galván, R. Picker, M. L. Pitt, B. Plaster, J. C. Ramsey, R. Rios, A. Saunders, S. J. Seestrom, E. I. Sharapov, W. E. Sondheim, E. Tatar, R. B. Vogelaar, B. VornDick, C. Wrede, A. R. Young, B. A. Zeck. 2012-10-26. Precision Measurement of the Neutron Beta-Decay Asymmetry. https://doi.org/10.1103/physrevc.87.032501

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