Simulation Methods for Transverse Beam Size Measurements Using the Heterodyne Near Field Speckles of Hard X-rays

The Heterodyne Near Field Speckles (HNFS) is a special type of interferometry technique where radiation is scattered by nanoparticles suspended in a medium. The scattered waves and the transmitted radiation form an interference pattern, which is modulated by the spatial coherence of the radiation and by the scattering properties of the nanoparticles. The superposition of many such interference patterns results in a speckle pattern, from which the spatial coherence of the radiation and thus the transverse beam profile can be determined. In this contribution we present approaches for simulating the HNFS patterns from hard X-ray radiation and compare then with data from experiments at the ALBA synchrotron.