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A solution to the inversion problem of scattering would offer aberration-free diffraction-limited 3D images without the resolution and depth-of-field limitations of lens-based tomographic systems. Powerful algorithms are increasingly being…

By suitably generalizing the Fourier constraint projection in the difference map phasing algorithm, an object can be reconstructed from its diffraction pattern even when the latter has been incoherently averaged over a discrete group of…

Data Analysis, Statistics and Probability · Physics 2007-05-23 Veit Elser

The general and practical inversion of diffraction data-producing a computer model correctly representing the material explored - is an important unsolved problem for disordered materials. Such modeling should proceed by using our full…

Materials Science · Physics 2016-07-05 Anup Pandey , Parthapratim Biswas , David A. Drabold

An algorithm for determining crystal structures from diffraction data is described which does not rely on the usual Fourier-space formulations of atomicity. The new algorithm implements atomicity constraints in real-space, as well as…

Condensed Matter · Physics 2007-05-23 Veit Elser

Ultrafast scattering using X-rays or electrons is an emerging method to obtain structure dynamics at the atomic length and time scales. However, directly resolving in real-space atomic motions is inherently limited by the finite detector…

Atomic Physics · Physics 2023-02-09 Adi Natan

We experimentally demonstrate how to solve the phase problem of diffraction using multi-wave interference with standard diffraction experimental setups without the need for taking any auxiliary data. In particular, we show that the phases…

Optics · Physics 2021-05-04 M. Fally , Y. Tomita , A. Fimia , R. F. Madrigal , J. Guo , J. Kohlbrecher , J. Klepp

Matrix inversion problems are often encountered in experimental physics, and in particular in high-energy particle physics, under the name of unfolding. The true spectrum of a physical quantity is deformed by the presence of a detector,…

Machine Learning · Statistics 2020-09-08 Pietro Vischia

A method is presented to precisely reconstruct charge spectra with pixel detectors using binary hit information of individual pixels. The method is independent of the charge information provided by the readout circuitry and has a resolution…

Instrumentation and Detectors · Physics 2017-02-17 David-Leon Pohl , Jens Janssen , Tomasz Hemperek , Fabian Hügging , Norbert Wermes

Any object on earth has two fundamental properties: it is finite, and it is made of atoms. Structural information about an object can be obtained from diffraction amplitude measurements that account for either one of these traits.…

Optics · Physics 2015-05-13 S. Marchesini

Most existing learning-based methods for solving imaging inverse problems can be roughly divided into two classes: iterative algorithms, such as plug-and-play and diffusion methods leveraging pretrained denoisers, and unrolled architectures…

Image and Video Processing · Electrical Eng. & Systems 2026-03-31 Matthieu Terris , Samuel Hurault , Maxime Song , Julian Tachella

X-ray crystallography (XC) is an experimental technique used to determine three-dimensional crystalline structures. The acquired data in XC, called diffraction patterns, is the Fourier magnitudes of the unknown crystalline structure. To…

Image and Video Processing · Electrical Eng. & Systems 2019-07-09 Samuel Pinilla , Jorge Bacca , Cesar Vargas , Juan Carlos Poveda-Jaramillo , Henry Arguello

We propose a direct imaging method based on the reverse time migration to reconstruct extended obstacles in the half space with finite aperture elastic scattering data at a fixed frequency. We prove the resolution of the reconstruction…

Numerical Analysis · Mathematics 2019-07-24 Zhiming Chen , Shiqi Zhou

Phase reconstruction is important in transmission electron microscopy for structural studies. We describe electron Fourier ptychography and its application to phase reconstruction of both radiation-resistant and beam-sensitive materials. We…

We present a novel method for Ankylography: three-dimensional structure reconstruction from a single shot diffraction intensity pattern. Our approach allows reconstruction of objects containing many more details than was ever demonstrated,…

Optics · Physics 2012-03-22 Eliyahu Osherovich , Oren Cohen , Yonina C. Eldar , Mordechai Segev

The local and overall responses of nonlinear composites are classically investigated by the Finite Element Method. We propose an alternate method based on Fourier series which avoids meshing and which makes direct use of microstructure…

Computational Engineering, Finance, and Science · Computer Science 2020-12-17 H. Moulinec , Pierre Suquet

The topic of the paper is the position reconstruction from signals of segmented detectors. With the help of a simple simulation, it is shown that the position reconstruction using the centre-of-gravity method is strongly biased, if the…

Instrumentation and Detectors · Physics 2021-09-15 A. Ebrahimi , F. Feind , E. Fretwurst , E. Garutti , M. Hajheidari , R. Klanner , D. Pitzl , J. Schwandt , G. Steinbrueck , I. Zoi

A rigorous mathematical model and an efficient computational method are proposed to solving the inverse elastic surface scattering problem which arises from the near-field imaging of periodic structures. We demonstrate how an enhanced…

Analysis of PDEs · Mathematics 2017-12-08 Huaian Diao , Peijun Li , Xiaokai Yuan

Atomic-resolution imaging with scanning transmission electron microscopy is a powerful tool for characterizing the nanoscale structure of materials, in particular features such as defects, local strains, and symmetry-breaking distortions.…

We apply a new method "force enhanced atomic refinement" (FEAR) to create a computer model of amorphous silicon (a-Si), based upon the highly precise X-ray diffraction experiments of Laaziri et al. The logic underlying our calculation is to…

Materials Science · Physics 2016-12-28 Anup Pandey , Parthapratim Biswas , Bishal Bhattarai , D. A. Drabold

Modeling the large-scale structure of the universe on nonlinear scales has the potential to substantially increase the science return of upcoming surveys by increasing the number of modes available for model comparisons. One way to achieve…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-30 Marcel Schmittfull , Zvonimir Vlah
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