PSI, Villigen
The X-ray FEL facilities in an advanced stage of planning worldwide can be grouped in two categories. Those with normal conducting driver linacs aiming to bring the XFEL technology, after the impressive feasibility prove at LCLS, to regional user communities at affordable cost, and those with superconducting driver linacs capable to serve several photon hungry users simultaneously. The talk will review the rationales, technical choices and status of the main proposals and discuss some key R&D issues.
PSI, Villigen
The Swiss FEL linac consists of a 450 MeV S-band injector and of a main linac at the C-band frequency (5.712 GHz) aiming at a final energy of 5.8 GeV. The main linac is composed of 26 RF modules. Each module consists of a single 50 MW klystron and its solid-state modulator feeding a pulse compressor and four accelerating structures. The two-meter long C-band accelerating structures have 110 cells, including the two coupler cells, and operate with a 2π/3 phase advance. We report here on RF studies performed on the accelerating structures with different cell topologies and on the pulse compressor where a Barrel-Open Cavity (BOC) design is adopted. The power requirements for the different accelerating structures with the single and two-bunch operation are also presented.
CERN, Geneva
PSI, Villigen
IPM, Tehran
NU, Evanston
The CLIC Test Facility 3 (CTF3) is being built and commissioned by an international collaboration in order to test the feasibility of the proposed Compact Linear Collider (CLIC) two-beam acceleration scheme. The monitoring and control of the bunch length throughout the CTF3 complex is important since this affects the efficiency and the stability of the RF power production process. Bunch length diagnostics therefore form an essential component of the beam instrumentation at CTF3. This paper presents and compares longitudinal profile measurements based on transverse RF deflectors, Streak camera and non-destructive microwave spectrometry techniques.