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We suggest a two-dimensional wavelet devised to deduce the large-scale structure of a physical field (e.g., the Galactic magnetic field) from its integrals along straight paths from irregularly spaced data points to a fixed interior point…

Astrophysics · Physics 2009-11-07 R. Stepanov , P. Frick , A. Shukurov , D. Sokoloff

We investigate the use of wavelet-space feature decomposition in neural super-resolution for rendering pipelines. Building on recent neural upscaling frameworks, we introduce a formulation that predicts stationary wavelet coefficients…

Graphics · Computer Science 2025-09-23 Prateek Poudel , Prashant Aryal , Kirtan Kunwar , Navin Nepal , Dinesh Baniya Kshatri

We present a new detection algorithm based on the wavelet transform for the analysis of high energy astronomical images. The wavelet transform, due to its multi-scale structure, is suited for the optimal detection of point-like as well as…

Image deblurring is a classical computer vision problem that aims to recover a sharp image from a blurred image. To solve this problem, existing methods apply the Encode-Decode architecture to design the complex networks to make a good…

Image and Video Processing · Electrical Eng. & Systems 2021-10-13 Wenbin Zou , Mingchao Jiang , Yunchen Zhang , Liang Chen , Zhiyong Lu , Yi Wu

We construct a neural network to perform regression on the local dark-matter density field given line-of-sight peculiar velocities of dark-matter halos, biased tracers of the dark matter field. Our architecture combines a convolutional…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-27 Baptiste Barthe-Gold , Nhat-Minh Nguyen , Leander Thiele

Wavelet analysis is proposed as a new tool for studying the large-scale structure formation of the universe. To reveal its usefulness, the wavelet decomposition of one-dimensional cosmological density fluctuations is performed. In contrast…

Astrophysics · Physics 2009-10-28 Yoshi Fujiwara , Jiro Soda

One of the most efficient ways to produce unconditional simulations is with the kernel convolution using fast Fourier transform (FFT) [1]. However, when data is located on a surface, this approach is not efficient because data needs to be…

Computation · Statistics 2016-01-18 Alexander Gribov

We develop an algorithm for the reconstruction of the two-dimensional mass distribution of a gravitational lens from the observable distortion of background galaxies. From the measured reduced shear, the lens mapping is obtained, from which…

Astrophysics · Physics 2009-10-31 Tarun Deep Saini , Somak Raychaudhury

Masked Image Modeling (MIM) has garnered significant attention in self-supervised learning, thanks to its impressive capacity to learn scalable visual representations tailored for downstream tasks. However, images inherently contain…

Computer Vision and Pattern Recognition · Computer Science 2025-03-04 Wenzhao Xiang , Chang Liu , Hongyang Yu , Xilin Chen

We study the prospects for three-dimensional mapping of the dark matter to high redshift through the shearing of faint galaxies images at multiple distances by gravitational lensing. Such maps could provide invaluable information on the…

Astrophysics · Physics 2009-08-12 Wayne Hu , Charles R. Keeton

Weak gravitational lensing is considered to be one of the most powerful tools to study the mass and the mass distribution of galaxy clusters. However, weak lensing mass reconstructions are plagued by the so-called mass-sheet degeneracy--the…

Astrophysics · Physics 2007-05-23 M. Bradac , M. Lombardi , P. Schneider

In recent years, the rise in the number of Lyman Break Galaxies detected at high redshifts z >= 6 has opened up the possibility of understanding early galaxy formation physics in great detail. In particular, the faint-end slope (alpha) of…

Astrophysics of Galaxies · Physics 2018-10-17 Tirthankar Roy Choudhury , Pratika Dayal

In the imaging process of an astronomical telescope, the deconvolution of its beam or Point Spread Function (PSF) is a crucial task. However, deconvolution presents a classical and challenging inverse computation problem. In scenarios where…

Instrumentation and Methods for Astrophysics · Physics 2024-03-05 Shulei Ni , Yisheng Qiu , Yunchun Chen , Zihao Song , Hao Chen , Xuejian Jiang , Huaxi Chen

We have developed a new three-dimensional algorithm, based on the standard P$^3$M method, for computing deflections due to weak gravitational lensing. We compare the results of this method with those of the two-dimensional planar approach,…

Astrophysics · Physics 2009-10-31 H. M. P. Couchman , Andrew J. Barber , Peter A. Thomas

We infer gravitational lensing shear and convergence fields from galaxy ellipticity catalogs under a spatial process prior for the lensing potential. We demonstrate the performance of our algorithm with simulated Gaussian-distributed…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-19 Michael D. Schneider , Karen Y. Ng , William A. Dawson , Philip J. Marshall , Joshua Meyers , Deborah J. Bard

This paper reviews statistical methods recently developed to reconstruct and analyze dark matter mass maps from weak lensing observations. The field of weak lensing is motivated by the observations made in the last decades showing that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. Pires , J. -L. Starck , A. Refregier

Strong gravitational lensing provides a purely gravitational means to infer properties of dark matter halos and thereby constrain the particle nature of dark matter. Strong lenses sometimes appear as four lensed images of a background…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-20 Daniel Gilman , Simon Birrer , Anna Nierenberg , Maverick S. H. Oh

Laser-plasma interferograms are currently analyzed by extracting the phase-shift map with FFT techniques (K.A.Nugent, Applied Optics {\bf 18}, 3101 (1985)). This methodology works well when interferograms are only marginally affected by…

Plasma Physics · Physics 2016-09-08 P. Tomassini , A. Giulietti , L. A. Gizzi , M. Galimberti , D. Giulietti , M. Borghesi , O. Willi

Deep imaging of the diffuse light emitted by the stellar fine structures and outer halos around galaxies is now often used to probe their past mass assembly. Because the extended halos survive longer than the relatively fragile tidal…

Astrophysics of Galaxies · Physics 2017-05-10 Emin Karabal , Pierre-Alain Duc , Harald Kuntschner , Pierre Chanial , Jean-Charles Cuillandre , Stephen Gwyn