2021/06/22 by Francisco M. González, F. M. Gonzalez, E. M. Fries +59 · 1 citation
Physics and Astronomy · #Algorithm #Astronomy and Astrophysical Research #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #Computer science #Neutron #Nuclear physics #Pairing #Particle physics #Physics #Quantum mechanics #Quantum, superfluid, helium dynamics #Scientific Research and Discoveries #Stellar, planetary, and galactic studies #Ultracold neutrons #hep-ex #nucl-ex #nucl-th
paper · pdf · doi:10.1103/physrevlett.127.162501
7 pages, 2 figures, 3 tables
openalex publication_date 2021/06/22 · arxiv created 2021/09/21 · arxiv updated 2021/10/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In this work, we report an improved measurement of the free neutron lifetime τn using the UCNτ apparatus at the Los Alamos Neutron Science Center. We count a total of approximately 38×10<sup>6</sup> surviving ultracold neutrons (UCNs) after storing in UCNτ’s magnetogravitational trap over two data acquisition campaigns in 2017 and 2018. We extract τ<sub>n</sub> from three blinded, independent analyses by both pairing long and short storage time runs to find a set of replicate τ<sub>n</sub> measurements and by performing a global likelihood fit to all data while self-consistently incorporating the β-decay lifetime. Both techniques achieve consistent results and find a value τ<sub>n</sub>=877.75±0.28<sub>stat</sub>+0.22/–0.16<sub>syst</sub> s. With this sensitivity, neutron lifetime experiments now directly address the impact of recent refinements in our understanding of the standard model for neutron decay.