X-ray Multimodal Intrinsic-Speckle-Tracking

• Published in: arXiv.org
• Main Authors: Pavlov, Konstantin M, Paganin, David M, Li, Heyang, Berujon, Sebastien, Rougé-Labriet, Hélène, Brun, Emmanuel
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 15.09.2020
• Subjects: Optical flow (image analysis); Optical properties; Physics - Applied Physics; Physics - Optics; Refractivity; Small angle X ray scattering; Tracking; X ray optics
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1911.06814

We develop X-ray Multi-modal Intrinsic-Speckle-Tracking (MIST), a form of X-ray speckle-tracking that is able to recover both the position-dependent phase shift and the position-dependent small-angle X-ray scattering (SAXS) signal of a phase object. MIST is based on combining a Fokker-Planck description of paraxial X-ray optics, with an optical-flow formalism for X-ray speckle-tracking. Only two images need to be taken in the presence of the sample, corresponding to two different transverse positions of the speckle-generating membrane, in order to recover both the refractive and local-SAXS properties of the sample. Like the optical-flow X-ray phase-retrieval method which it generalises, the MIST method implicitly rather than explicitly tracks both the transverse motion and the diffusion of speckles that is induced by the presence of a sample. Application to X-ray synchrotron data shows the method to be efficient, rapid and stable.