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Related papers: Reconstruction in Fourier space

200 papers

Redshift space distortion (RSD) is a powerful way of measuring the growth of structure and testing General Relativity, but it is limited by cosmic variance and the degeneracy between galaxy bias b and the growth rate factor f. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Yan-Chuan Cai , Gary Bernstein

We have developed a new geometrical method for identifying and reconstructing a homogeneous and highly complete set of galaxy groups in the next generation of deep, flux-limited redshift surveys. Our method combines information from the…

Astrophysics · Physics 2009-11-07 Christian Marinoni , Marc Davis , Jeffrey A. Newman , Alison L. Coil

The well-known discrete Fourier transform (DFT) can easily be generalized to arbitrary nodes in the spatial domain. The fast procedure for this generalization is referred to as nonequispaced fast Fourier transform (NFFT). Various…

Numerical Analysis · Mathematics 2025-06-09 Melanie Kircheis , Daniel Potts

Nonuniform Fourier data are routinely collected in applications such as magnetic resonance imaging, synthetic aperture radar, and synthetic imaging in radio astronomy. To acquire a fast reconstruction that does not require an online inverse…

Numerical Analysis · Mathematics 2016-10-05 Anne Gelb , Guohui Song

Fourier reconstruction algorithms significantly outperform conventional back-projection algorithms in terms of computation time. In photoacoustic imaging, these methods require interpolation in the Fourier space domain, which creates…

Numerical Analysis · Mathematics 2016-11-17 M. Haltmeier , O. Scherzer , G. Zangerl

I present a method for the fast convolution of a model galaxy profile by a point-spread function (PSF) model represented as a pixel grid. The method relies upon three observations: First, most simple radial galaxy profiles of common…

Instrumentation and Methods for Astrophysics · Physics 2021-01-01 Dustin Lang

We present a modified version of the friends-of-friends (FOF) structure finding algorithm, designed specifically to locate groups or clusters of galaxies in photometric redshift datasets. The main objective of this paper is to show that…

Astrophysics · Physics 2009-11-10 C. S. Botzler , J. Snigula , R. Bender , U. Hopp

We present and implement the concept of the Fourier-domain dedispersion (FDD) algorithm, a brute-force incoherent dedispersion algorithm. This algorithm corrects the frequency-dependent dispersion delays in the arrival time of radio…

Instrumentation and Methods for Astrophysics · Physics 2022-01-05 C. G. Bassa , J. W. Romein , B. Veenboer , S. van der Vlugt , S. J. Wijnholds

Phase retrieval, a nonlinear problem prevalent in imaging applications, has been extensively studied using random models, some of which with i.i.d. sensing matrix components. While these models offer robust reconstruction guarantees, they…

Optics · Physics 2024-09-10 Zhiyuan Hu , Julián Tachella , Michael Unser , Jonathan Dong

Compressed Sensing (CS) significantly speeds up Magnetic Resonance Image (MRI) processing and achieves accurate MRI reconstruction from under-sampled k-space data. According to the current research, there are still several problems with…

Image and Video Processing · Electrical Eng. & Systems 2023-10-24 Junpeng Tan , Chunmei Qing , Xiangmin Xu

Objective:This study introduces a residual error-shifting mechanism that drastically reduces sampling steps while preserving critical anatomical details, thus accelerating MRI reconstruction. Approach:We propose a novel diffusion-based SR…

Computer Vision and Pattern Recognition · Computer Science 2026-01-16 Mojtaba Safari , Shansong Wang , Zach Eidex , Qiang Li , Erik H. Middlebrooks , David S. Yu , Xiaofeng Yang

Accurate modeling of small-scale redshift-space clustering is crucial for full shape RSD analyses, where satellite galaxies contribute to 1-halo terms and Finger-of-God distortions. We investigate halo reconstruction based on the cylinder…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-14 Ryuichiro Hada , Teppei Okumura

This work presents a fast and non-convex algorithm for robust subspace recovery. The data sets considered include inliers drawn around a low-dimensional subspace of a higher dimensional ambient space, and a possibly large portion of…

Machine Learning · Computer Science 2018-11-07 Gilad Lerman , Tyler Maunu

In this paper a sublinear time algorithm is presented for the reconstruction of functions that can be represented by just few out of a potentially large candidate set of Fourier basis functions in high spatial dimensions, a so-called…

Numerical Analysis · Mathematics 2020-06-24 Lutz Kämmerer , Felix Krahmer , Toni Volkmer

The Gridding algorithm has shown great utility for reconstructing images from non-uniformly spaced samples in the Fourier domain in several imaging modalities. Due to the non-uniform spacing, some correction for the variable density of the…

Image and Video Processing · Electrical Eng. & Systems 2021-06-17 Nicholas Dwork , Daniel O'Connor , Ethan M. I. Johnson , Corey A. Baron , Jeremy W. Gordon , John M. Pauly , Peder E. Z. Larson

In this paper we study the performance of image reconstruction methods from incomplete samples of the 2D discrete Fourier transform. Inspired by requirements in parallel MRI, we focus on a special sampling pattern with a small number of…

Numerical Analysis · Mathematics 2025-10-22 Gerlind Plonka , Anahita Riahi

Faraday tomography through broadband polarimetry can provide crucial information on magnetized astronomical objects, such as quasars, galaxies, or galaxy clusters. However, the limited wavelength coverage of the instruments requires that we…

Instrumentation and Methods for Astrophysics · Physics 2022-08-17 Suchetha Cooray , Tsutomu T. Takeuchi , Shinsuke Ideguchi , Takuya Akahori , Yoshimitsu Miyashita , Keitaro Takahashi

To fully extract cosmological information from nonlinear galaxy distribution in redshift space, it is essential to include higher-order statistics beyond the two-point correlation function. In this paper, we propose a new decomposition…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-20 Naonori S. Sugiyama , Shun Saito , Florian Beutler , Hee-Jong Seo

Accurate modelling of redshift-space distortions (RSD) is challenging in the non-linear regime for two-point statistics e.g. the two-point correlation function (2PCF). We take a different perspective to split the galaxy density field…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-14 Enrique Paillas , Yan-Chuan Cai , Nelson Padilla , Ariel Sánchez

In this work, we test a framework to perform the analysis of redshift-space distortions simultaneously in configuration and Fourier space. We test our methods with the AbacusSummit suite of N-body simulations as well as a more numerous set…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-25 Vincenzo Aronica , Julian E. Bautista , Arnaud de Mattia , Hector Gil-Marín