Generation of tunable dual X-ray pulses in synchrotron light sources

Synchrotron light sources are powerful platforms for cutting-edge, multidisciplinary research, with dozens currently in operation, construction or commissioning worldwide. It is widely recognized that different research areas have specific demands for source capabilities. For the majority of synchrotron facilities, delivering high-brightness, high-flux synchrotron radiation stably through high-current electron beams is the primary mode of operation. However, there is also a significant demand for timing experiments to study dynamic processes. In response, many synchrotron facilities offer specialized or hybrid timing modes. In this paper, we propose a novel method that combines a double RF system and deflecting cavities to generate pairs of X-ray pulses in electron storage rings with adjustable transverse separation and time delay. This approach holds the potential to enable new experimental possibilities, such as X-ray pump and X-ray probe studies, or capturing information from two temporal points in a dynamic process using two X-ray probes simultaneously. We analyze the fundamental characteristics of this method, present a conceptual design, and demonstrate through simulations that the scheme can achieve adjustable transverse separation of the two X-ray pulses with tunable time delay on the order of 100 ps.