http://arxiv.org/abs/1812.09671
We construct the error distributions for the neutron lifetime using a subset of measurements compiled in the 2018 edition of Particle Data Group (PDG), as well as a few recent measurements, which are not yet included in PDG. We then checked the Gaussianity of the error distribution (using the techniques pioneered by Ratra and collaborators). We find that the error distributions using the weighted mean as well as median estimate are not consistent with a Gaussian distribution. We find that the Student’s $t$ and Cauchy distribution provide a better fit to the residuals. We then argue that median statistics based estimate should be used for the central estimate of the neutron lifetime. This median statistic estimate of the neutron lifetime from these measurements is given by $881.5 \pm 0.47$ seconds. We also note that the discrepancy between beam and bottle-based measurements using median statistics based estimates of the neutron lifetime persists to between 4-8$\sigma$, depending on which combination of measurements are used.
A. Rajan and S. Desai
Thu, 27 Dec 18
9/80
Comments: 5 pages