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Atoms 2018, 6(4), 70;

Measurements of the Neutron Lifetime

Department of Physics and Engineering Physics, Tulane University, New Orleans, LA 70118, USA
Received: 7 November 2018 / Revised: 1 December 2018 / Accepted: 4 December 2018 / Published: 10 December 2018
(This article belongs to the Special Issue High Precision Measurements of Fundamental Constants)
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Free neutron decay is a fundamental process in particle and nuclear physics. It is the prototype for nuclear beta decay and other semileptonic weak particle decays. Neutron decay played a key role in the formation of light elements in the early universe. The precise value of the neutron mean lifetime, about 15 min, has been the subject of many experiments over the past 70 years. The two main experimental methods, the beam method and the ultracold neutron storage method, give average values of the neutron lifetime that currently differ by 8.7 s (4 standard deviations), a serious discrepancy. The physics of neutron decay, implications of the neutron lifetime, previous and recent experimental measurements, and prospects for the future are reviewed. View Full-Text
Keywords: neutron decay; neutron lifetime; beta decay neutron decay; neutron lifetime; beta decay

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Wietfeldt, F.E. Measurements of the Neutron Lifetime. Atoms 2018, 6, 70.

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