A new method for measuring the neutron lifetime using an in situ neutron detector.
C L MorrisE R AdamekL J BroussardN B CallahanS M ClaytonC Cude-WoodsS A CurrieX DingW FoxK P HickersonM A HoffbauerA T HolleyA KomivesC-Y LiuM MakelaR W PattieJ RamseyD J SalvatA SaundersS J SeestromE I SharapovS K SjueZ TangJ VanderwerpB VogelaarP L WalstromZ WangWanchun WeiJ W WexlerT L WomackA R YoungB A ZeckPublished in: The Review of scientific instruments (2018)
In this paper, we describe a new method for measuring surviving neutrons in neutron lifetime measurements using bottled ultracold neutrons (UCN), which provides better characterization of systematic uncertainties and enables higher precision than previous measurement techniques. An active detector that can be lowered into the trap has been used to measure the neutron distribution as a function of height and measure the influence of marginally trapped UCN on the neutron lifetime measurement. In addition, measurements have demonstrated phase-space evolution and its effect on the lifetime measurement.