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Related papers: Image Rotation from weak Lensing

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Radio polarization measurements of pulsed emission from pulsars offer a valuable insight into the basic geometry of the neutron star: inclination angle between the magnetic and rotation axis and inclination of the line of sight. So far, all…

High Energy Astrophysical Phenomena · Physics 2017-01-11 J. Pétri

Polarization measurements from relativistic outflows are a valuable tool to probe the geometry of the emission region and the microphysics of the particle distribution. Indeed, the polarization level depends on: (i) the local magnetic field…

High Energy Astrophysical Phenomena · Physics 2015-12-03 Lara Nava , Ehud Nakar , Tsvi Piran

We develop and test a method for measuring the gravitational lensing induced distortion of faint background galaxies. We first describe how we locate the galaxies and measure a 2-component `polarisation' or ellipticity statistic $e_\alpha$…

Astrophysics · Physics 2009-10-16 Nick Kaiser , Gordon Squires , Tom Broadhurst

Weak gravitational lensing is the slight distortion of galaxy shapes caused primarily by the gravitational effects of dark matter in the universe. In our work, we seek to invert the weak lensing signal from 2D telescope images to…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-22 Brandon Zhao , Aviad Levis , Liam Connor , Pratul P. Srinivasan , Katherine L. Bouman

In this paper we present the theoretical basis for the modeling of weakly gravitationally lensed extended sources that are polarized. This technique has been used in the past to constrain the mass profiles of galaxies projected against the…

We report the discovery of a new gravitationally lensed radio source. Radio maps of MG0751+2716 show four lensed images, which, at higher resolution, are resolved into long arcs of emission. A group of galaxies is present in optical images,…

General relativity predicts that gravitational lensing near black holes will produce narrow "photon rings" on images. Building on recent work of Johnson, Lupsasca et al. focusing on circular rings, I calculate the long-baseline…

High Energy Astrophysical Phenomena · Physics 2020-08-12 Samuel E. Gralla

We calculate the polarization of radiation from thick accretion disks with vertically averaged global magnetic field. The polarization arises as a result of the radiation scattering by free electrons in magnetized plasma of a disk. We…

Astrophysics · Physics 2007-05-23 Yu. N. Gnedin , N. A. Silant'ev , P. S. Shternin

The measurement of shape parameters of sources in astronomical images is usually performed by assuming that the underlying noise is uncorrelated. Spatial noise correlation is however present in practice due to various observational effects…

Astrophysics · Physics 2007-05-23 A. Refregier , S. T. Brown

The low-frequency polarisation properties of radio sources are poorly studied, particularly in statistical samples. However, the new generation of low-frequency telescopes, such as the Murchison Widefield Array (MWA; the precursor for the…

Modern dual-polarization receivers allow a radio telescope to characterize the full polarization state of incoming insterstellar radio waves. Many astronomers incorrectly consider a polarimeter to be the "backend" of the telescope. We go to…

Instrumentation and Methods for Astrophysics · Physics 2021-10-13 Timothy Robishaw , Carl Heiles

The PVLAS collaboration has observed rotation of the plane of polarization of light passing through a magnetic field in vacuum and has proposed that the effect is due to interaction of photons with very light spin-zero bosons. This would…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. V. Afanasev , O. K. Baker , K. W. McFarlane , G. H. Biallas , J. R. Boyce , M. D. Shinn

General Relativity predicts only two tensor polarization modes for gravitational waves while at most six possible polarization modes are allowed in general metric theory of gravity. The number of polarization modes is determined by the…

General Relativity and Quantum Cosmology · Physics 2022-06-08 Chao Zhang , Yungui Gong , Dicong Liang , Chunyu Zhang

Gravitational field can cause a rotation of polarisation plane of light. This phenomenon is known as the gravitational Faraday effect. We study the gravitational Faraday effect of linearly polarised light propagating in the gravitational…

General Relativity and Quantum Cosmology · Physics 2022-06-20 Andrey A. Shoom

A method is given which renders indirect detection of strong gravitational waves possible. This is based on the reflection (collision) of a linearly polarized electromagnetic shock wave from (with) a cross polarized impulsive and shock…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Mustafa Halilsoy , Ozay Gurtug

The main goal of the present paper is to study how polarization of photons affects their motion in a gravitational field created by a rotating massive compact object. We study propagation of the circularly polarized beams of light in a…

General Relativity and Quantum Cosmology · Physics 2011-09-08 Valeri P. Frolov , Andrey A. Shoom

When gravitational waves propagate near massive objects, their paths curve resulting in gravitational lensing, which is expected to be a promising new instrument in astrophysics. If the time delay between different paths is comparable with…

General Relativity and Quantum Cosmology · Physics 2022-07-14 Oleg Bulashenko , Helena Ubach

We study gravitational lensing by quadrupole potentials within the linearized gravity approximation and the integration over the unperturbed photon trajectory. It is well known that the quadrupole potential contribution to the deviation…

Astrophysics · Physics 2007-05-23 Davor Palle

Polarization is one of the fundamental natures of electromagnetic radiation. The detection of polarization or polarized photons from distant X-ray radiating systems (such as X-ray binaries (XBs), active galactic nuclei (AGN), pulsars, and…

High Energy Astrophysical Phenomena · Physics 2026-01-01 Arbind Pradhan , Sree Bhattacherjee , Biplob Sarkar

Inhomogeneities can influence the polarisation emerging from a synchrotron source. However, it is shown that the frequency distribution of circular polarisation is only marginally affected, although its magnitude may change substantially.…

High Energy Astrophysical Phenomena · Physics 2020-05-13 C. -I. Bjornsson
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