Single-Bunch Imaging Of Detonation Fronts Using Scattered Synchrotron Radiation

A centimeter-scale field of view for transmission X-ray radiography from a sub-millimeter-focused synchrotron X-ray beam is achieved by placing a strongly scattering material upstream of the sample. Combining the scattered beam with a detector system synchronized and gated to acquire images from single X-ray pulses provides the capability for time-resolved observations of transient phenomena in samples larger than the native X-ray beam. Furthermore, switching between this scatter-beam imaging (SBI) and scattering modes is trivial compared to switching between unfocused white beam imaging and scattering using a focused pink beam. As a result, SBI additionally provides a straightforward method to precisely align samples relative to the focused X-ray beam for subsequent small-angle X-ray scattering measurements. This paper describes the use of glassy carbon for SBI to observe phenomena during detonation of small-scale high explosive charges and compares the technique to conventional white beam imaging. SBI image sequences from ideal versus non-ideal explosive materials provide insights into the evolution of dead zones of the undetonated material, while tomographic reconstructions of radiographs acquired as the detonation front traverses the explosive charge can provide a means for estimating the density at and behind the detonation front. Published by AIP Publishing.