Electrostatic Deflectors for Luminosity Measurements at the Cern pp Collider

Electrostatic deflectors are used in the CERN SPS Collider to separate the orbits of protons and antiprotons. The total installation comprises 4 tanks, 3 m long each, with a vacuum of 10-8 Pa after baking. The operating electric field is 50 kV/cm across a gap of 4 cm, between 3 m long titanium electrodes; the spark rate does not exceed 2 per 24 hours. The construction, the HV circuit, and the performances of the separators are described in this paper.