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Forthcoming radio surveys will include full polarisation information, which can be potentially useful for weak lensing observations. We propose a new method to measure the (integrated) gravitational field between a source and the observer,…

Astrophysics of Galaxies · Physics 2021-12-08 Jérémie Francfort , Giulia Cusin , Ruth Durrer

A general and rigorous method to deal with singularities at the origin of a polar coordinate system is presented. Its power derives from a clear distinction between the radial distance and the radial coordinate variable, which makes that…

Classical Physics · Physics 2007-05-23 Andre Gsponer

Radio sources are often polarized. Accurate measurement of simply the flux density of a radio source requires a basic understanding of polarization and its measurement techniques. We provide an introductory, heuristic discussion of these…

Astrophysics · Physics 2007-05-23 Carl Heiles

A joint action of depth and bandwidth depolarization in the interstellar medium is considered using a model of N homogeneous synchrotron layers with Faraday rotation. The bandwidth depolarization can be used in multifrequency polarimetric…

Astrophysics · Physics 2007-05-23 E. N. Vinyajkin

The purpose of this work is to provide theoretically grounded assessment on both the field-of-view and the bandwidth of a lensless holographic setup. Indeed, while previous works have presented results with super-resolution and…

Signal Processing · Electrical Eng. & Systems 2021-03-23 Ferréol Soulez

Researchers routinely characterize optical samples by computing the scattering cross-section. However, the experimental determination of this magnitude requires the measurement and integration of the components of the scattered field in all…

In this letter, we demonstrate the experimental mapping of the longitudinal magnetic and electric optical fields with a standard scanning microscope that involves a high numerical aperture far-field objective. The imaging concept relies…

Optics · Physics 2015-06-17 C. Ecoffey , T. Grosjean

Coronagraphy is an efficient technique for identifying and characterizing extra-solar planets orbiting in the habitable zone of their parent star. An important family of coronagraphs is based on amplitude or phase filters placed at an…

Instrumentation and Methods for Astrophysics · Physics 2022-08-30 Francçois Henault

In this talk I describe a recently introduced field-theoretical approach that can be used as an alternative framework to study one-dimensional systems of highly correlated particles.

High Energy Physics - Theory · Physics 2009-10-30 Carlos M. Naon

Several local elliptic coordinates are used to build a new polyelliptic coordinate system which is orthogonal and admits the separation of variables. Such coordinate systems can give the exact solutions of some unsolved problems in quantum…

Mathematical Physics · Physics 2014-09-25 Gennady V. Kovalev

A simple method to generate a two-dimensional binary grid pattern, which allows for absolute and accurate self-location in a finite planar region, is proposed. The pattern encodes position information in a local way so that reading a small…

Information Theory · Computer Science 2011-12-20 Alfred M. Bruckstein , Tuvi Etzion , Raja Giryes , Noam Gordon , Robert J. Holt , Doron Shuldiner

Several projects in radioastronomy plan to use large static cylindrical reflectors with an extended lobe sampling a sector of the rotating sky. This study provides the exact mathematical expression of the transit time of a celestial object…

Instrumentation and Methods for Astrophysics · Physics 2012-09-03 Marc Moniez

It is commonplace in cosmology to analyze fields projected onto the celestial sphere, and in particular density fields that are defined by a set of points e.g. galaxies. When performing an harmonic-space analysis of such data (e.g. an…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-02 Antón Baleato Lizancos , Martin White

Stereoscopic spectral imaging is an observing technique that affords rapid acquisition of limited spectral information over an entire image plane simultaneously. Light from a telescope is dispersed into multiple spectral orders, which are…

Astrophysics · Physics 2007-05-23 Craig E. DeForest , Charles C. Kankelborg

Using full-wave numerical simulations and analytical multipole expansions we investigated the properties of real-space polarization singularities that emerge in light scattering by subwavelength particles. We considered spherical and torus…

Optics · Physics 2021-02-18 Jie Peng , Wei Liu , Shubo Wang

A new technique based on superposition of two speckle patterns is proposed and demonstrated for controlled modulation of the spatial polarization distribution of the resultant speckle. It is demonstrated both theoretically and…

Optics · Physics 2021-11-15 Abhijit Roy , Rakesh K. Singh , Maruthi M. Brundavanam

The polarization state of the optical electromagnetic field lying several nanometers above complex dielectric structures reveals the intricate light-matter interaction that occurs in this near-field zone. This information can only be…

Polarimetry in the far-infrared and submillimeter has been valuable in tracing magnetic fields in bright Galactic Clouds. We discuss the techniques we have developed and trends we have found in polarization vs column density, and vs…

Astrophysics · Physics 2015-06-24 Roger Hildebrand

We discuss some basic principles of stereoscopy and their relevance to the reconstruction of coronal loops. The aim of the paper is to make the solar physicist familiar with basic stereoscopy principles and to give hints how they may apply…

Astrophysics · Physics 2007-05-23 Bernd Inhester

Relativistic positioning systems are interesting {\em technical objects} for applications around the Earth and in the Solar system. But above all else, they are basic {\em scientific objects} allowing developing relativity from its own…

General Relativity and Quantum Cosmology · Physics 2013-02-26 Bartolomé Coll