Neutron lifetime from a new evaluation of ultracold neutron storage experiments

An analysis of data on measurements of neutron lifetime is presented. The new most accurate result of the measurement of neutron lifetime [Phys. Lett. B 605, 72 (2005)] $878.5\pm 0.8$ s, differs from the world average value [Phys. Lett. B 667, 1 (2008)] $885.7\pm 0.8$ s, by 6.5 standard deviations. In this connection an analysis and Monte Carlo simulation of experiments [Phys. Lett. B 483, 15 (2000)] and [Phys. Rev. Lett. 63, 593 (1989)] is carried out. Systematic errors of about $-6$ s are found in each of the experiments. A summary table of neutron lifetime measurements after corrections and additions is given. A new world average value for neutron lifetime, $879.9\pm 0.9$ s, is presented. DOI: http://dx.doi.org/10.1103/PhysRevC.82.035501 © 2010 The American Physical Society