English
Related papers

Related papers: Strong Lensing Reconstruction

200 papers

Detailed measurements of the CMB lensing signal are an important scientific goal of ongoing ground-based CMB polarization experiments, which are mapping the CMB at high resolution over small patches of the sky. In this work we simulate CMB…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-30 Ruth Pearson , Blake Sherwin , Antony Lewis

Recovering a signal from its Fourier intensity underlies many important applications, including lensless imaging and imaging through scattering media. Conventional algorithms for retrieving the phase suffer when noise is present but display…

Image and Video Processing · Electrical Eng. & Systems 2020-03-05 Yaotian Wang , Xiaohang Sun , Jason W. Fleischer

It is usually assumed that the ellipticity power spectrum measured in weak lensing observations can be expressed as an integral over the underlying matter power spectrum. This is true at second order in the gravitational potential. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Elisabeth Krause , Christopher M. Hirata

In this third paper of a series on radio weak lensing for cosmology with the Square Kilometre Array, we scrutinise synergies between cosmic shear measurements in the radio and optical/near-IR bands for mitigating systematic effects. We…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Stefano Camera , Ian Harrison , Anna Bonaldi , Michael L. Brown

A new non-linear optimization approach is proposed for the sparse reconstruction of log-conductivities in current density impedance imaging. This framework comprises of minimizing an objective functional involving a least squares fit of the…

Optimization and Control · Mathematics 2020-06-30 Madhu Gupta , Rohit Kumar Mishra , Souvik Roy

In the field of data mining, how to deal with high-dimensional data is an inevitable problem. Unsupervised feature selection has attracted more and more attention because it does not rely on labels. The performance of spectral-based…

Machine Learning · Computer Science 2021-01-01 Zhengxin Li , Feiping Nie , Jintang Bian , Xuelong Li

Accurately reconstructing a global spatial field from sparse data has been a longstanding problem in several domains, such as Earth Sciences and Fluid Dynamics. Historically, scientists have approached this problem by employing complex…

Computer Vision and Pattern Recognition · Computer Science 2024-08-23 Robert Sunderhaft , Logan Frank , Jim Davis

Lensless cameras provide a framework to build thin imaging systems by replacing the lens in a conventional camera with an amplitude or phase mask near the sensor. Existing methods for lensless imaging can recover the depth and intensity of…

Image and Video Processing · Electrical Eng. & Systems 2021-08-19 Yucheng Zheng , Yi Hua , Aswin C. Sankaranarayanan , M. Salman Asif

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

Polarization imaging is a technique that creates a pixel map of the polarization state in a scene. Although invisible to the human eye, polarization can assist various sensing and computer vision tasks. Existing polarization cameras use…

Image and Video Processing · Electrical Eng. & Systems 2026-03-19 Noa Kraicer , Shay Elmalem , Erez Yosef , Hani Barhum , Raja Giryes

Upcoming ground-based cosmic microwave background experiments will provide CMB maps with high sensitivity and resolution that can be used for high fidelity lensing reconstruction. However, the sky coverage will be incomplete and the noise…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-11 Mark Mirmelstein , Julien Carron , Antony Lewis

In this investigation we focus on the problem of mapping the ground reflectivity with multiple laser scanners mounted on mobile robots/vehicles. The problem originates because regions of the ground become populated with a varying number of…

Computer Vision and Pattern Recognition · Computer Science 2017-03-10 Juan Castorena

We present a systematic analysis of the constraints $\sigma_\gamma$ on the mass profile slope $\gamma$ obtainable when fitting a singular power-law ellipsoid model to a typical strong lensing observation of an extended source. These results…

Astrophysics of Galaxies · Physics 2020-06-24 Conor M. O'Riordan , Stephen J. Warren , Daniel J. Mortlock

Quantifying image distortions caused by strong gravitational lensing and estimating the corresponding matter distribution in lensing galaxies has been primarily performed by maximum likelihood modeling of observations. This is typically a…

Instrumentation and Methods for Astrophysics · Physics 2017-09-20 Yashar D. Hezaveh , Laurence Perreault Levasseur , Philip J. Marshall

Weak lensing mass-mapping from shear catalogs faces systematic challenges from survey masks and spatially varying noise. To overcome these issues and reconstruct unbiased convergence $\kappa$ maps, we have constructed the AKRA (Accurate…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-23 Yuan Shi , Pengjie Zhang , Zhao Chen , Jian Qin , Li Cui , Furen Deng , Ji Yao

Current optical imaging surveys for cosmology are covering large areas of sky. To exploit the statistical power of these surveys for weak lensing measurements requires shape measurement methods with subpercent systematic errors. We…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 Ricardo Herbonnet , Axel Buddendiek , Konrad Kuijken

Weak lensing convergence maps - upon which higher order statistics can be calculated - can be recovered from observations of the shear field by solving the lensing inverse problem. For typical surveys this inverse problem is ill-posed…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-08 Matthew A. Price , Xiaohao Cai , Jason D. McEwen , Thomas D. Kitching

It is now routine to measure the weak gravitational lensing shear signal from the mean ellipticity of distant galaxies. However, conversion between ellipticity and shear assumes local linearity of the lensing potential (ie that the spatial…

Astrophysics · Physics 2010-11-11 Richard Massey , David M. Goldberg

We address the problem of signal reconstruction from intensity measurements with respect to a measurement frame. This non-convex inverse problem is known as phase retrieval. The case considered in this paper concerns phaseless measurements…

Functional Analysis · Mathematics 2019-02-13 Goetz E. Pfander , Palina Salanevich

We propose an approach for dense semantic 3D reconstruction which uses a data term that is defined as potentials over viewing rays, combined with continuous surface area penalization. Our formulation is a convex relaxation which we augment…

Computer Vision and Pattern Recognition · Computer Science 2019-08-27 Nikolay Savinov , Christian Haene , Lubor Ladicky , Marc Pollefeys