Neutrino beam of the Institute of High-Energy Physics. IV. Focusing device of the neutrino channel

The system for producing the neutrino beam at the accelerator of the Institute of High-Energy Physics is described. The basic characteristics and structural features of the neutrino focusing device are described. This device consists of three objectives made of parabolic lenses. Current pulses up to 0.5 mA with a length of 160 ..mu..sec pass through the lenses. Data on the operation of the focusing device are reported. The ratio of the muon fluxes in the shielding in the cases with and without focusing ranges from 4 to 30, depending on the momentum. This ratio is a measure of the operation of the neutrino focusing device.