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Measurement of the neutron lifetime using a gravitational trap and a low-temperature Fomblin coating

A. Serebrov·V. Varlamov·A. Kharitonov·A. Fomin·Yu. Pokotilovski·P. Geltenbort·J. Butterworth·I. Krasnoschekova·M. Lasakov·R. Taldaev·A. Vassiljev·O. Zherebtsov
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Abstract

We present a new value for the neutron lifetime of 878.5 +- 0.7 stat. +- 0.3 syst. This result differs from the world average value (885.7 +- 0.8 s) by 6.5 standard deviations and by 5.6 standard deviations from the previous most precise result. However, this new value for the neutron lifetime together with a beta-asymmetry in neutron decay, Ao, of -0.1189(7) is in a good agreement with the Standard Model.

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A. Serebrov, V. Varlamov, A. Kharitonov, A. Fomin, Yu. Pokotilovski, P. Geltenbort, J. Butterworth, I. Krasnoschekova, M. Lasakov, R. Taldaev, A. Vassiljev, O. Zherebtsov. 2004-09-02. Measurement of the neutron lifetime using a gravitational trap and a low-temperature Fomblin coating. https://doi.org/10.1016/j.physletb.2004.11.013

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