Optimization of laser-based synchrotron X-ray for plant imaging

Abstract

X-ray computed tomography of plants requires a high number of X-ray photons, good source stability, and a large field of view. We show that we can optimize a laser-based synchrotron X-ray source for this application. The X-ray beam is produced during electron acceleration by laser wakefield. These results were obtained using 160 TW on-target laser peak power, $$4.6\times 10^{19}\,\text {W cm}^{-2}$$ laser pulse intensity, and nitrogen gas target. We measured a critical energy $$\sim$$ 15 keV, enough X-ray photons to realize an image with one single laser shot, more than 50 mrad divergence, a good shot to shot stability and spatial distribution homogeneity required for tomography imaging. The gas jet target pressure is low enough to use the laser system at the laser nominal repetition rate (2.5 Hz). We produced a micrometer X-ray source size that allows high resolution (< 20 $$\upmu$$ m) and phase contrast imaging.