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Measuring the Neutron Lifetime with Magnetically Trapped Ultracold Neutrons
Published
Author(s)
Hans P. Mumm
Abstract
We describe an experiment to measure the neutron lifetime using a technique with a set of systematic uncertainties largely different than those of previous measurements. In this approach, UCN are produced by inelastic scattering of cold (0.89 nm) neutrons in a reservoir of superfluid 4He. These neutrons are then confined using a three-dimensional magnetic trap. As the trapped neutrons beta decay, the energetic electrons produced in the decay generate scintillations in the liquid He; each decay is detectable with nearly 100 % efficiency. The neutron lifetime can be directly determined by measuring the scintillation rate as a function of time.
Proceedings Title
Workshop on Next Generation Experiments to Measure the Neutron
Lifetime
Mumm, H.
(2013),
Measuring the Neutron Lifetime with Magnetically Trapped Ultracold Neutrons, Workshop on Next Generation Experiments to Measure the Neutron
Lifetime, Sante Fe, NM, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=914531
(Accessed October 13, 2025)