K-edge imaging based on a Thomson scattering x-ray source

Abstract

A Thomson scattering X-ray source can produce quasi-monochromatic and continuously energy-tunable X-rays characterized by small focal spot and high brightness, which makes it an excellent light source for K-edge imaging. In this paper, the experimental feasibility of K-edge imaging was demonstrated at the Tsinghua Thomson scattering X-ray source (TTX). The phantom was a plastic test tube filled with sodium iodide (NaI)- loaded water solutions with I concentrations ranging from 5 to 300 mg/ml. Well agreement between the measured equivalent projection integral of the linear attenuation coefficient of the phantom and the theoretically predicted value was witnessed. The influence of X-ray bandwidth on the image quality was discussed. Based on the continuous tunability of scattered X-ray energy, the K-edge subtraction imaging was tested and obvious contrast enhancement was achieved. Our results pave the way towards practical application of K-edge imaging at the TTX.