Partial Test of the PS Complex as LHC Proton Injector

The CERN Large Hadron Collider (LHC) will be supplied with protons from the injector chain Linac 2 -PS Booster (PSB) -PS-SPS.The beam must have small transverse emittances to fit into the tiny LHC dynamic aperture, and sufficient intensity for high-luminosity operation: the required beam brilliance is about twice that of current PS beams.In principle such a beam is feasible by a scheme [1][2) involving acceleration of one bunch in each of the four PSB rings to a kinetic energy raised from 1 to 1.4 GeV, two-batch filling of the PS, and acceleration on new RF harmonics (8 and 16) in the PS to 26 GeV∕c.This approach was tested during a 12-day machine development session (ÌLHC Testi) in December 1993 [31, for which hardware had been prepared as prototypes, using only one PSB ring and a low cycle repetition rate.During this LHC Test, virtually all ingredients of the scheme proved to work as anticipated.Comprehensive sets of beam profile measurements under various machine conditions are presented together with consequences for the proposed LHC filling scheme.