“Real-life” pulse flattening on the LLNL Flash X-ray (FXR) machine

High-resolution radiography using high-current electron accelerators based on the linear induction accelerator principle requires the linac’ final spot on the X-ray target to be millimeter-sized. The requisite final focusing solenoid is adjusted for a specific beam energy at its entrance, hence, temporal variation of entrance beam energy results in a less than optimal time-averaged spot size.