Measurement of the Free Neutron Lifetime using the Neutron Spectrometer on NASA's Lunar Prospector Mission
Abstract
We use data from the Lunar Prospector Neutron Spectrometer to make the second space-based measurement of the free neutron lifetime finding τn=887 14stat\:+7-3\:syst s, which is within 1σ of the accepted value. This measurement expands the range of planetary bodies where the neutron lifetime has been quantified from space, and by extending the modeling to account for non-uniform elemental composition, we mitigated a significant source of systematic uncertainty on the previous space-based lifetime measurement. This modeling moves space-based neutron lifetime measurement towards the ultimate goal of reducing the magnitude of the systematics on a future space-measurement to the level of those seen in laboratory-based experiments.
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