ELETTRA, Basovizza
Uni LJ, Ljubljana
The FERMI@Elettra injector, comprised of a high-gradient, s-band, photo-cathode rf gun, the PC gun driven laser, the first two accelerating sections, controls, and suite of diagnostics has been commissioned in 2009. The electron beam has been characterized in terms of charge, energy, energy spread and transverse emittance, and results are provided in this paper. In early 2010 linac commissioning up to 250MeV continued, and by using the RF deflecting cavity, the slice parameters of the beam have been measured. Moreover, studies on the laser pulse shaping and the relative optimization of the longitudinal ramp profile required by the nominal bunch configuration are presented in this paper.
University of Ljubljana, Faculty of Electrical Engineering, Ljubljana
I-Tech, Solkan
The new generation of accelerators requires timing distribution and RF synchronization with femtosecond precision in terms of jitter and long-term stability. The proposed electro-optical synchronization system makes use of commercial telecom single-mode optical fibre operating at 1550 nm.. It operates on over 300 m distance. It consists of a transmitter, located near a low-jitter master oscillator, and receiver, located at the remote location. The field experiments have been done in the accelerator environment with the fibre pair in the tunnel. The prototype units were installed at the same location to make phase difference measurement simple. Temperature in various installation points, phase difference and both units internal operational parameters were continuously monitored and stored. Data was post-analysed and conclusions were used for hardware changes and mostly the long-term stability improvement. A dedicated phase detector was designed to monitor less than 20 fs changes. Results are showing 80 fs RMS and 30 fs stability over 20 and 8 hours respectively. The prototype is being redesigned for manufacturing with some new features for improved long-term stability.