The Compact Linear Collider (CLIC) study collaboration has for the first time sent beam right to the end of the drive beamline in the CLIC Test Facility (CTF3). Early in the afternoon of 3 September, all eyes in the CTF3 control room were fixed on the camera display that showed a small beam-profile screen installed at the far end of their accelerator complex. A few minutes later the first bunch of electrons was lighting up this monitor.
Building on this success, a major effort will now go into commissioning the whole CTF3 complex to reach nominal beam parameters. CLIC’s accelerating principle is based on a two-beam scheme: a drive beam provides power for the accelerating structures, which accelerate the main beam. The programme for CTF3 foresees bringing the linac into operation for initial acceleration of the main beam, then installing and testing a first decelerating structure in the drive-beam line.