On the project of measuring the neutron lifetime (τn) within an error of δτn≅±3s in the experiment on cold neutron beam transport in the field-free space

A possibility is shown for measuring the neutron lifetime (τn) within an error of ±3s in the cold neutron beam experiment. Methods for measuring the quantities determining neutron density (Qs), efficiency (ε) of observation of neutron decay events, permeability (η) of grids and counting rates (np) of recoiling protons were approved earlier. The errors in measurements of these quantities in the cold neutron beam experiment (on example of the ILL reactor beam) have been analyzed, and it has been found that their contribution to the τn error are δQs=±0.22%, δε=±0.1%, δη=±0.08%, δnp=±0.14% respectively. 15 refs.; 4 figs.; 1 tab