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We study the image formation process with the solar gravitational lens (SGL) in the case of an extended, resolved source. An imaging telescope, modeled as a convex lens, is positioned within the image cylinder formed by the light received…

Instrumentation and Methods for Astrophysics · Physics 2020-07-31 Slava G. Turyshev , Viktor T. Toth

Given a set of images, whose pixel values can be considered as the components of a vector, it is interesting to estimate the modulus of such a vector in some localised areas corresponding to a compact signal. For instance, the…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 F. Argueso , J. L. Sanz , D. Herranz , M. Lopez-Caniego , J. Gonzalez-Nuevo

We study the problem of deconvolution for light-sheet microscopy, where the data is corrupted by spatially varying blur and a combination of Poisson and Gaussian noise. The spatial variation of the point spread function (PSF) of a…

A new method is proposed to get image features' geometric information. Using Gaussian as an input signal, a theoretical optimal solution to calculate feature's affine shape is proposed. Based on analytic result of a feature model, the…

Computer Vision and Pattern Recognition · Computer Science 2015-03-19 Xiaopeng Xu , Xiaochun Zhang

In order to improve the fit to the optical counts, the multi-wavelength source count model of Rowan-Robinson (2001) is improved in two ways. First, density evolution is incorporated to correspond to the mergers in hierarchical models of…

Astrophysics · Physics 2009-11-07 A. J. King , M. Rowan-Robinson

We propose a new, two-stage algorithm for inverting strong gravitational lenses. The key to the algorithm is decoupling the effects of lens magnification and intrinsic structure in the background source in the appearance of lensed arcs.…

Astrophysics · Physics 2007-05-23 P. Newbury , G. G. Fahlman

We consider nonparametric measurement error density deconvolution subject to heteroscedastic measurement errors as well as symmetry about zero and shape constraints, in particular unimodality. The problem is motivated by applications where…

Methodology · Statistics 2020-02-19 Ya Su , Anirban Bhattacharya , Yan Zhang , Nilanjan Chatterjee , Raymond J. Carroll

Parallel slit-slit devices are commonly used to measure the transverse emittance of a particle beam, selecting a portion of the beam with the front slit and measuring the angular distribution with the rear. This paper calculates the effect…

Accelerator Physics · Physics 2016-01-12 Richard D'Arcy , Alexander Shemyakin

Any characterization of a single-photon source is not complete without specifying its second-order degree of coherence, i.e., its $g^{(2)}$ function. An accurate measurement of such coherence functions commonly requires high-precision…

Quantum Physics · Physics 2009-09-12 M. Razavi , I. Söllner , E. Bocquillon , C. Couteau , R. Laflamme , G. Weihs

Diffraction tomography aims to recover an object's scattering potential from measured wave fields. In the classical setting, the object is illuminated by plane waves from many directions, and the Fourier diffraction theorem provides a…

Numerical Analysis · Mathematics 2026-03-11 Peter Elbau , Noemi Naujoks

In long adaptive optics corrected exposures, exoplanet detections are currently limited by speckle noise originating from the telescope and instrument optics, and it is expected that such noise will also limit future high-contrast imaging…

Astrophysics · Physics 2009-11-13 C. Marois , D. Lafreniere , B. Macintosh , R. Doyon

Analytic expressions of the spatial coherence of partially coherent fields propagating in the Fresnel regime in all but the simplest of scenarios are largely lacking and calculation of the Fresnel transform typically entails tedious…

In this work we present a new algorithm for data deconvolution that allows the retrieval of the target function with super-resolution with a simple approach that after a precis e measurement of the instrument response function (IRF), the…

Computer Vision and Pattern Recognition · Computer Science 2018-12-07 Sandra Martínez , Oscar E. Martínez

A unified description of the free-space cylindrical vector beams is presented, which is an integral transformation solution to the vector Helmholtz equation and the transversality condition. The amplitude 2-form of the angular spectrum…

Optics · Physics 2009-11-13 Chun-Fang Li

We investigate the conformal algebra on the fuzzy sphere, and in particular the generators of translations and special conformal transformations which are emergent symmetries in the infinite IR but are broken along the RG flow. We show how…

High Energy Physics - Theory · Physics 2025-08-22 Giulia Fardelli , A. Liam Fitzpatrick , Emanuel Katz

Ultrasound is widely used in medical diagnostics allowing for accessible and powerful imaging but suffers from resolution limitations due to diffraction and the finite aperture of the imaging system, which restricts diagnostic use. The…

Computer Vision and Pattern Recognition · Computer Science 2024-08-08 Felix Duelmer , Walter Simson , Mohammad Farid Azampour , Magdalena Wysocki , Angelos Karlas , Nassir Navab

We show that the use of the electromagnetic inverse source framework offers great flexibility in the design of metasurfaces. In particular, this approach is advantageous for antenna design applications where the goal is often to satisfy a…

Applied Physics · Physics 2019-10-17 Trevor Brown , Chaitanya Narendra , Yousef Vahabzadeh , Christophe Caloz , Puyan Mojabi

In this paper, we propose a novel design of image deblurring in the form of one-shot convolution filtering that can directly convolve with naturally blurred images for restoration. The problem of optical blurring is a common disadvantage to…

Image and Video Processing · Electrical Eng. & Systems 2019-07-22 Mahdi S. Hosseini , Konstantinos N. Plataniotis

Bayesian approaches are one of the primary methodologies to tackle an inverse problem in high dimensions. Such an inverse problem arises in hydrology to infer the permeability field given flow data in a porous media. It is common practice…

Methodology · Statistics 2023-10-02 Navid Shervani-Tabar

Interferometers from the ground and space will be able to resolve the two images in a microlensing event. This will at least partially lift the inherent degeneracy between physical parameters in microlensing events. To increase the…

Astrophysics · Physics 2016-08-30 N. J. Rattenbury , S. Mao