High Performance Electronics for Alignment Regulation on the CLIC 30GHz modules

The general outline of the High Performance Electronics for the Alignment System of the linear collider CLIC is presented. What is also shown are its most important characteristics. The main objective is to have a global view of the problems and the solutions found. The details of each of the subsystems and boards that compose the electronics will be published later

Active Alignment Electronic System for CLIC 30 GHz Modules in CTF2

The active alignment system is capable of positioning accelerator components of CLIC (Compact Linear Collider) with a precision of a few microns. An electronic processing and command system connects the micro-movers and sensors of this system to the CERN-PS complex control system

Active Alignment System for CLIC 30 GHz Modules in CTF2

The active alignment system is capable of positioning accelerator components of CLIC (Compact Linear Collider) with a few micron precision. An electronic processing and command system connects the micro-movers and sensors of this system to the CERN-PS complex control system

An Active Pre-Alignment System and Metrology Network for CLIC

The pre-alignment tolerance on the transverse positions of the components of the CLIC linacs is typically ten microns over distances of 200 m. Such tight tolerances cannot be obtained by a static one-time alignment because normal seismic ground movement and cultural noise associated with human and industrial activity quickly creates significant errors. It is therefore foreseen to maintain the components in place using an active-alignment system which will be linked to a permanent metrology and geodetic network. This report describes the overall philosophy and implementation of such a system and proposes one possible solution for active-alignment which uses stepping-motors to move components and stretched-wires as reference lines. Special sensors have been developed to measure the position of the components with respect to the reference lines, and to measure local tilt and relative vertical position. An in-depth analysis has been made of the repercussions on the alignment system of perturbing effects due to the attraction of the moon and the sun, and of the presence of nearby geological masses. The active-alignment system was used to maintain the components of the 30 GHz Two-Beam Test Accelerator in position in the CLIC Test Facility CTF2 as a practical demonstration of successful operation in an accelerator environment. The hardware and control system that was built for this application are described together with the results obtained

An Injector for the CLIC Test Facility (CTF3)

The CLIC Test Facility (CTF3) is an intermediate step to demonstrate the technical feasibility of the key concepts of the new RF power source for CLIC. CTF3 will use electron beams with an energy range adjustable from 170 MeV (3.5 A) to 380 MeV (with low current). The injector is based on a thermionic gun followed by a classical bunching system embedded in a long solenoidal field. As an alternative, an RF photo-injector is also being studied. The beam dynamics studies on how to reach the stringent beam parameters at the exit of the injector are presented. Simulations performed with the EGUN code showed that a current of 7 A can be obtained with an emittance less than 10 mm.mrad at the gun exit. PARMELA results are presented and compared to the requested beam performance at the injector exit. Sub-Harmonic Bunchers (SHB) are foreseen, to switch the phase of the bunch trains by 180 degrees from even to odd RF buckets. Specific issues of the thermionic gun and of the SHB with fast phase switch are discussed

AN INJECTOR FOR THE CLIC TEST FACILITY (CTF3)

Abstract The CLIC Test Facility (CTF3) is an intermediate step to demonstrate the technical feasibility of the key concepts of the new RF power source for CLIC. CTF3 will use electron beams with an energy range adjustable from 170 MeV (3.5 A) to 380 MeV (with low current). The injector is based on a thermionic gun followed by a classical bunching system embedded in a long solenoidal field. As an alternative, an RF photo-injector is also being studied. The beam dynamics studies on how to reach the stringent beam parameters at the exit of the injector are presented. Simulations performed with the EGUN code showed that a current of 7 A can be obtained with an emittance less than 10 mm.mrad at the gun exit. PARMELA results are presented and compared to the requested beam performance at the injector exit. SubHarmonic Bunchers (SHB) are foreseen, to switch the phase of the bunch trains by 180 degrees from even to odd RF buckets. Specific issues of the thermionic gun and of the SHB with fast phase switch are discussed

CLIC: a Two-Beam Multi-TeV e±e\pm Linear Collider

The CLIC study of a high-energy (0.5 - 5 TeV), high-luminosity (1034 - 1035 cm-2 sec-1) e+e- linear collider is presented. Beam acceleration using high frequency (30 GHz) normal-conducting structures operating at high accelerating fields (150 MV/m) significantly reduces the length and, in consequence, the cost of the linac. Using parameters derived from general scaling laws for linear colliders, the beam stability is shown to be similar to lower frequency designs in spite of the strong wake-field dependency on frequency. A new cost-effective and efficient drive beam generation scheme for RF power production by the so-called "Two-Beam Acceleration" method is described. It uses a thermionic gun and a fully-loaded normal-conducting linac operating at low frequency (937 MHz) to generate and accelerate the drive beam bunches, and RF multiplication by funnelling in compressor rings to produce the desired bunch structure. Recent 30 GHz hardware developments and CLIC Test Facility (CTF) results are described

CTF3 Design Report: Preliminary Phase

The design of CLIC is based on a two-beam scheme, where the short pulses of high power 30 GHz RF are extracted from a drive beam running parallel to the main beam. The 3rd generation CLIC Test Facility (CTF3) will demonstrate the generation of the drive beam with the appropriate time structure, the extraction of 30 GHz RF power from this beam, as well as acceleration of a probe beam with 30 GHz RF cavities. The project makes maximum use of existing equipment and infrastructure of the LPI complex, which became available after the closure of LEP. In the first stage of the project, the "Preliminary Phase", the existing LIL linac and the EPA ring, both modified to suit the new requirements, are used to investigate the technique of frequency multiplication by means of interleaving bunches from subsequent trains. This report describes the design of this phase