Fill and dump measurement of the neutron lifetime using an asymmetric magneto-gravitational trap

Alexander Komives, DePauw University
Christopher Morris, Los Alamos National Laboratory
et al.

Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization: USDOE Laboratory Directed Research and Development (LDRD) Program
DOE Contract Number: 89233218CNA000001
OSTI ID: 2377332
Report Number(s): LA-UR-22-23486
Country of Publication: United States
Language: English

Abstract

The past two decades have yielded several new measurements and reanalysis of older measurements of the neutron lifetime. These have led to a 4.4 standard deviation discrepancy between the most precise measurements of the neutron decay rate producing protons in cold neutron beams and the most precise lifetime measured in neutron storage experiments. Measurements using different techniques are important for investigating whether there are unidentified systematic effects in any of the measurements. In this paper we report a new measurement using the Los Alamos asymmetric magnetogravitational trap where the surviving neutrons are counted external to the trap using the fill and dump method. The new measurement gives a free neutron lifetime of ______ . Although this measurement is not as precise, it is in statistical agreement with previous results using in situ counting in the same apparatus.