Simulation Study of an LWFA-based Electron Injector for AWAKE Run 2

The AWAKE experiment aims to demonstrate preservation of injected electron beam quality during acceleration in proton-driven plasma waves. The short bunch duration required to correctly load the wakefield is challenging to meet with the current electron injector system, given the space available to the beamline. An LWFA readily provides short-duration electron beams with sufficient charge from a compact design, and provides a scalable option for future electron acceleration experiments at AWAKE. Simulations of a shock-front injected LWFA demonstrate a 43 TW laser system would be sufficient to produce the required charge over a range of energies beyond 100 MeV. LWFA beams typically have high peak current and large divergence on exiting their native plasmas, and optimisation of bunch parameters before injection into the proton-driven wakefields is required. Compact beam transport solutions are discussed.Comment: Paper submitted to NIMA proceedings for the 3rd European Advanced Accelerator Concepts Workshop. 4 pages, 3 figures, 1 table Changes after revision: Figure 2: figures 2 and 3 of the previous version collated with plots of longitudinal electric field Line 45: E_0 = 96 GV/m Lines 147- 159: evaluation of beam loading made more accurate Lines 107 - 124: discussion of simulation geometry move

Design and optimisation of the Compact Linear Collider main LINAC module for micron-level stability and alignment

The Compact Linear Collider (CLIC) study is developing a Multi-TeV e+e- linear collider. An acceleration gradient of 100 MV m-1will be achieved in the Main LINACs using 11.994 GHz Super Accelerating Structures (SAS). To achieve the required luminosity, the SAS will be prealigned within modules to less than 14 mu m and maintain their position to within 1.4 mu m when exposed to local sources of mechanical noise. A module design is presented and Finite Element Analysis (FEA) is used to optimise the harmonic frequencies of this module and thereby minimise the potential impact of unknown sources of vibration. A module with a fundamental frequency of 60 Hz is presented. Historical ground noise data from the LHC at CERN is used to statistically quantify the magnitude of SAS misalignments unavoidably induced by local ground noise. The one-standard -deviation average vertical misalignment due to ground noise is less than 0.044 mu m above 0.1 Hz for all SAS.Peer reviewe

Work on PETS Developed at CIEMAT

CIEMAT has been working on the RF power extractor so-called PETS (Power Extraction and Transfer Structure) for the CLIC Test Facility 3 (CTF3) since 2007. The first contribution has been installed at the Test Beam Line (TBL). Additionally, a new PETS configuration is presently under fabrication at CIEMAT and will be installed in the Test Module at CTF3. This paper describes the PETS prototypes design, fabrication and assembly techniques. The characterization of the devices with low RF power is also described.Comment: 9 pages, 9 figures, 3 tables, 10 references. Work presented in the LCWS1

CLIC Wake Field Monitor as a detuned Cavity Beam Position Monitor: Explanation of center offset between TE and TM channels in the TD26 structure

The Wake Field Monitor (WFM) system installed on the CLIC prototype accelerating structure in CERN Linear Accelerator for Research (CLEAR) has two channels for each horizontal/vertical plane, operating at different frequencies. When moving the beam relative to the aperture of the structure, a disagreement is observed between the center position of the structure as measured with the two channels in each plane. This is a challenge for the planned use of WFMs in the Compact Linear Collider (CLIC), where they will be used to measure the center offset between the accelerating structures and the beam. Through a mixture of simulations and measurements, we have discovered a potential mechanism for this, which is discussed along with implications for improving position resolution near the structure center, and the possibility determination of the sign of the beam offset.Comment: 16 pages, 20 figure

Status and plans of the Compact Linear Collider Study

The Compact Linear Collider (CLIC) project is exploring the possibility of constructing a multiTeV linear electron-positron collider for high-energy frontier physics studies beyond the LHC era. The CLIC concept is based on high-gradient normal-conducting accelerating structures. The RF power for the acceleration of the colliding beams is produced by a two-beam acceleration scheme, where power is extracted from a high current drive beam that runs parallel with the main linac. The key ongoing studies involve accelerator parameter optimisation, technical studies and component development, alignment and stability, and include a number of system performance studies in test-facilities around the world. The CLIC physics potential and main detector issues, as well as possible implementation staging, are being studied in parallel. A summary of the progress and status of the corresponding studies will be given, as well as an outline of the preparation and work towards developing a CLIC implementation plan by 2018/1

CLIC X-band technology developments and their use in compact accelerators for research, medicine and industry.

The CLIC study has developed compact, high gradient and energy efficient acceleration units as building blocks for a high energy linear collider for high-energy physics. Many of these components are now available in industry. These properties promise cost effective solutions for small linear accelerators in a variety of applications. The CLIC study actively promoted and supported such spin-off developments from the beginning. The applications include beam manipulation and diagnostic in research linacs such as FEL light sources, compact Compton-scattering x-ray sources, medical linacs for cancer treatment and compact neutron sources for material investigations. is contribution will introduce the x-band technologies developed and discuss examples of its use in some of the applications