The development of Z_eff imaging using a crystal X-ray interferometer

Abstract

Z_eff imaging that provides a way to visualize elemental distributions in samples has been developed. Because the atomic number (Z) of a single-element sample [the effective atomic number (Z_eff) for a multiple-element sample] corresponds to the ratio of the real to imaginary part of the complex refractive index, an elemental map is calculable from the ratio of absorption and phase-contrast images. Several metal foils underwent feasibility observations with an imaging system fitted with a two-crystal X-ray interferometer. The obtained Z_eff image shows that aluminum, iron, nickel, and copper foils were clearly distinguished and that the nickel and copper Z_eff values coincided with the ideal Z number within 5%.