In the framework of EuPRAXIA@SPARC_LAB project, we are studying possible solutions to upgrade and measure the amplitude and phase stability of the RF accelerating fields generated by a klystron. These studies concern the C- and X- band klystrons installed in the LNF infrastructures. In particular, we will present our work on a fast phase feedback around the C-band power station (50 MW klystron and solid state modulator) installed at SPARC_LAB. We are trying to push the timing jitter below the standard limit of such systems (few tens of fs RMS). A second topic is the study of the jitter of the X-band power station (50 MW klystron and solid state modulator) installed in the TEX facility. Precise measurements on amplitude and phase of this system will be reported at different positions both upstream (LLRF and pre-amp) and downstream (waveguides and prototype structure) the klystron.

The CW electron accelerator ELBE is in operation for more than two decades. The timing system has been patched several times in order to meet changing requirements. In 2019 the development of a new timing system based on Micro Research Finland Hardware has been started which is designed to unify the heterogeneous structure and to replace obsolete components. In spring 2024 the system has been put in user operation. The contribution will discuss the commissioning process and first experiences from the routine operation.

The timing system is a critical element in scientific facilities such as particle accelerators or laser ignition installations. The different subsystems that integrate these scientific facilities need to have a common notion of time. This common time reference is provided by the timing system. Thanks to that, it is possible to operate the machine in a time coherent manner and to properly track the different events that occur during the operation of the machine. The timing system also provides the discrete triggering events and periodic signals requested for the different subsystems. Furthermore, it can be used also for radiofrequency distribution across the facility. In this work it is presented the timing system architecture, based on the White Rabbit technology and currently under development by Safran Electronic & Defense Spain SLU, for the distribution of synchronized triggers. The hardware, based on FPGA, will be detailed. The timing system allows total triggering configuration in terms of direction, number of pulses, pulse rate, pulse period and delay offering a resolution in the order of 5 ps. The White Rabbit technology provides sub-nanosecond accuracy and picosecond precision in addition to important characteristics such as automatic link calibration. The performance achieved will be shown in this work.

X-ray Free Electron Lasers (XFELs) are transformative across multiple disciplines, offering high power and tunable wavelengths. Facilities like FLASH, LCLS, and SwissFEL, including China’s SXFEL and SHINE, provide ultra-bright femtosecond X-ray pulses. Their operation hinges on the precise synchronization of RF and laser sources, typically using femtosecond lasers as the master clock generator. Environmental factors such as temperature, pressure, and vibrations induce timing jitter, impacting the laser chain and experimental outcomes. Laser Arrival-time Measurement (LAM) technology precisely tracks and compensates for these variations, ensuring stability and accuracy. LAM’s precision is vital for XFEL performance enhancement and future facility development. The paper reviews the current state of LAM technology at SXFEL, analyzes the impact of environmental factors on stability, and looks forward to future developments, emphasizing the importance of LAM technology in advancing XFEL facility performance and scientific research.