| Paper | Title | Page |
|---|---|---|
| TUPD032 | Single Bunch Wakefields in the CERN-PSI-ELETTRA X-band Linear Accelerator | 1997 |
|
||
|
FERMI@ELETTRA and PSI-XFEL are 4th Generation Light Sources that require high quality electron beam at the entrance of the undulator chains. In this context, a specially developed X-band structure with integrated alignment monitors will be used to mitigate the nonlinearities in the longitudinal phase space due to the second order RF time curvature and the second order momentum compaction term of chicane compressor. The knowledge of the transverse and longitudinal short range wakefields in the X-band structure is essential to evaluate the beam quality in terms of longitudinal energy spread and transverse kick spread. We have used the ABCI code to numerically evaluate the transverse and longitudinal wake potentials for short bunches in this structure. |
||
| WEPE032 | Recent Progress on a Manifold Damped and Detuned Structure for CLIC | 3425 |
|
||
|
Our earlier design* for an accelerating structure to suppress the wakefields in the CLIC main accelerating cavities has been modified. This structure combines strong detuning of the cell frequencies with waveguide-like damping by providing the structure with four attached manifolds which loosely couple a portion of the wakefields from each cell. The amended geometry reduces the surface pulse temperature heating by approximately 20%. We report on the overall parameters of the fundamental mode, together with details on damping higher order dipole modes. In order to adequately suppress the wakefield we interleave the frequencies of eight successive structures. * Khan and Jones, TU5PFP007, PAC'09, Vancouver, Canada 2009. |
||
| THPEA042 | Engineering Design of a Multipurpose X-band Accelerating Structure | 3771 |
|
||
|
PSI-XFEL and Elettra-Fermi-require a X-band RF structure. As CLIC is pursuing a program for producing and testing x-band high-gradient RF structures, a collaboration between PSI, Elettra and CERN, has been established to build a multipurpose X-band accelerating structure. This paper focuses on its engineering design which is based on disk-shaped cells bonded together by different technologies (diffusion bonding, vacuum brazing and laser beam welding). The accelerating structure consists of 2 coupler subassemblies and 73 disks, and include wake field monitor waveguides. The engineering study also comprises the external cooling system, consisting of two parallel cooling circuits, and the tuning system, allowing for the fine-tuning by means of cell deformations. The engineering solution for installation and sealing of wake field monitor feed-through devices inside the accelerating structure RF-cavity is also proposed. |
||
| THPEA013 | Advances in X-band TW Accelerator Structures Operating in the 100 MV/m Regime | 3702 |
|
||
|
A CERN-SLAC-KEK collaboration on high gradient X-band accelerator structure development for CLIC has been ongoing for three years. The major outcome has been the demonstration of stable 100 MV/m gradient operation of a number of CLIC prototype structures. These structures were fabricated basically using the technology developed from 1994 to 2004 for the GLC/NLC linear collider initiative. One goal has been to refine the essential parameters and fabrication procedures needed to realize such high gradient routinely. Another goal has been to develop structures with stronger dipole mode damping than those for GLC/NLC. The latter requires that surface temperature rise during the pulses be higher, which may increase the breakdown rate. Structures with heavy damping will be tested in late 2009/early 2010, and this paper will present these results together with some of the earlier results from non-damped structures and structures built with a quadrant geometry. |