ABSTRACT High-energy X-ray flash radiography utilizes short-pulse high-energy X-rays generated by an accelerator to capture snapshots of fast-moving dense objects, enabling the inference of their internal geometric structures and density distributions from radiographic images. There is a strong motivation for providing multiple (two or more) time-sequenced images of implosion dynamics along the same axis from each large-scale hydrodynamic experiment to understand the physical process. This paper presents the design and operational results of a high-energy triple-pulse X-ray flash radiography source, Dragon-II. Dragon-II is the first ultrahigh-power multipulse linear induction accelerator (LIA) with an adjustable pulse interval in the world. It was designed and built in the mid-2010s to study hydrodynamic phenomena. During the development of Dragon-II, a series of technical challenges were creatively solved, including the generation of high-voltage pulses at a MHz repetition rate in burst mode, the establishment of multi-pulse acceleration fields, the generation, transportation, and focusing of multi-pulse high-current beams, as well as the effective conversion of multi-pulse X-rays. Continuous operation over the past ten years shows that Dragon-II is an effective, reliable, and low-maintenance ultrahigh-power multi-pulse LIA system.
Jianjun et al. (Mon,) studied this question.