The ratio R-dp of the quasi-elastic nd ->(nn)p to the elastic np -> np charge-exchange differential cross sections over the 0.8-2.0 Gev neutron beam nergy interval

New experimental results on the ratio R-dp of the charge-exchange quasi-elastic scattering yield at 0 degrees for the nd -> (nn) + p reaction to the elastic np -> np scattering yield are presented. These two charge -exchange angular dependences measured in a vicinity of the incident neutron direction, corrected for well known instrumental effects and extrapolated towards the incident neutron direction, are proportional to the differeiltial cross sections of the two relevant reactions. The measurements were carried out at the Nuclotron of the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research (JINR) at the neutron beam kinetic energies of 0.8, 1.0, 1.2, 1.4, 1.8 and 2.0 GeV. The intense quasi-monochromatic neutron beam was produced by break-up of accelerated deuterons extracted to the experimental area. The data were accumulated using the "Delta-Sigma" set-up magnetic spectrometer with two sets of multiwire proportional chambers, located upstream and downstream of the analyzing magnet. Inelastic processes were considerably reduced by detectors surrounding either the hydrogen, or deuterium targets. The time-of-flight system was used for detected particle identification. The data treatment and analysis of possible systematic errors are discussed. The obtained R-dp values remain nearly constant with energy. The new data are compared with existing ones, measured only at energies below 1 GeV.