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Published on: August 6, 2021
Measurement of the Neutron Lifetime by Counting Trapped Protons
F E Wietfeldt1, M S Dewey2, D M Gilliam2
1Tulane University, New Orleans, LA 70118.
Abstract:
We measured the neutron decay lifetime by counting in-beam neutron decay recoil protons trapped in a quasi-Penning trap. The absolute neutron beam fluence was measured by capture in a thin (6)LiF foil detector with known efficiency. The combination of these measurements gives the neutron lifetime: τ n = (886.8 ± 1.2 ± 3.2) s, where the first (second) uncertainty is statistical (systematic) in nature. This is the most precise neutron lifetime determination to date using an in-beam method.
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