Dealing with the high-brightness beam and space charge in CLIC

In the Compact Linear Collider (CLIC), space-charge forces play a role only in the injection complex and in the test facility, which reproduces at low energy the conditions of the CLIC scheme. Some numerical and experimental results are presented. The major question remains the emittance preservation of the high-brightness beam accelerated in the main linac. The strategy adopted, based on detailed studies of the magnetic and microwave focusing as well as on the development of elaborate trajectory corrections, is summarized. The resulting pre-alignment conditions and final position tolerances can be fulfilled by the pre-alignment schemes and micron-displacement systems which are being tested.