Uppsala University, Uppsala
At CERN the feasibility of CLIC (Compact LInear Collider) a multi-TeV electron-positron collider is being studied. In this scheme the RF power to accelerate the main beam is produced by a high current drive beam. To demonstrate this scheme a test facility (CLIC Test Facility 3, CTF3) has been constructed at CERN. Recently, the complex to generate the drive beam has been successfully commissioned producing a beam with a current around 30A. This beam is now being used to test the power production. The results of the test facility provide vital input for the CLIC conceptual design report to be finished by the end of 2010. This talk describes CTF3 activities and their importance for CLIC; it comments on design readiness for CLIC after a successful CTF3 demonstration.
CEA, Gif-sur-Yvette
CERN, Geneva
Uppsala University, Uppsala
The probe beam LINAC, CALIFES, of the CLIC Test Facility (CTF3) has been developed by CEA Saclay, LAL Orsay and CERN to deliver trains of short bunches (0.75 ps) spaced by 0.666 ps at an energy around 170 MeV with a charge of 0.6 nC to the TBTS (Two-beam Test Stand) intended to test the high gradient CLIC accelerating structures. Based on 3 former LIL accelerating structures and on a newly developed RF photo-injector, the whole accelerator is powered with a single 3 GHz klystron delivering pulses of 45 MW through a RF pulse compression cavity and a network of waveguides, splitters, phase-shifters and an attenuator. We relate here results collected during the various commissioning and operation periods which led to nominal performances and stable beam characteristics delivered to the TBTS. Progress has been made in the laser system for beam charge and stability, in space charge compensation for emittance, in RF compression law for energy and energy spread. The installation of a specially developed RF power phase shifter for the first accelerating structure used in velocity bunching allows the control of the bunch length.
ESS, Lund
IPN, Orsay
BNL, Upton, Long Island, New York
MSL, Stockholm
CEA, Gif-sur-Yvette
Fundación TEKNIKER, Eibar (Gipuzkoa)
INFN/LNS, Catania
ISA, Aarhus
SPRI, Bilbao
Uppsala University, Uppsala
JLAB, Newport News, Virginia
Following selection of Lund as the site for the long-pulse ESS (European Spallation Source), a team of accelerator and target experts has been working on an update of the 2003 ESS linac design. Improvements to the 2003 design will be summarised, and the latest designs for the linac will be presented.
CEA, Gif-sur-Yvette
CERN, Geneva
Uppsala University, Uppsala
PSI, Villigen
To achieve high luminosity in CLIC, the accelerating structures must be aligned to an RMS accuracy of 5 μm with respect to the beam trajectory. Position detectors called Wakefield Monitors (WFM) are integrated to the structure for a beam based alignment. This paper describes the requirements of such monitors. The development plan and basic feature of the WFM as well as the accelerating structure working at 12 GHz and 100 MV/m are shortly described. Then we focus on detailed electromagnetic simulations and design of the WFM itself. In particular, time domain computations are performed and an evaluation of the intrinsic resolution is done for two higher order modes at 17 and 24 GHz. The mechanical design of the accelerating structure with WFM is also presented. Precise machining with a tolerance of 2.5 μm and a surface roughness of 0.025 μm is demonstrated. The fabrication status of three complete accelerating structures with WFM is finally presented for a feasibility demonstration with beam in CTF3 at CERN.