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Related papers: The Microarcsecond Sky and Cosmic Turbulence

200 papers

We study the wave optics features of gravitational microlensing by a binary lens composed of a planet and a parent star. In this system, the source star near the caustic line produces a pair of images in which they can play the role of…

Earth and Planetary Astrophysics · Physics 2015-06-05 Ahmad Mehrabi , Sohrab Rahvar

Diffractive and refractive magnetospheric scintillations may allow a direct testing of the plasma inside the light cylinder. Unusual electrodynamics of the strongly magnetized electron-positron plasma allow separation of the magnetospheric…

Astrophysics · Physics 2009-10-31 Maxim Lyutikov

A strong case has been made that radio waves from sources within about half a degree of the Galactic Center undergo extreme diffractive scattering. However, problems arise when standard (``Kolmogorov'') models of electron density…

Astrophysics · Physics 2009-11-11 Peter Goldreich , S. Sridhar

Extreme Scattering Events and pulsar secondary spectra have highlighted fundamental problems in our understanding of the dynamics of interstellar turbulence. We describe some of these problems in detail and present the theory behind the…

Astrophysics of Galaxies · Physics 2015-06-11 Jean-Pierre Macquart

Intensity interferometry permits very long optical baselines and the observation of sub-milliarcsecond structures. Using planned kilometric arrays of air Cherenkov telescopes at short wavelengths, intensity interferometry may increase the…

Instrumentation and Methods for Astrophysics · Physics 2015-03-17 Dainis Dravins , Hannes Jensen , Stephan LeBohec , Paul D. Nuñez

We present simulations of scattering phenomena which are important in pulsar observations, but which are analytically intractable. The simulation code, which has also been used for solar wind and atmospheric scattering problems, is…

Astrophysics of Galaxies · Physics 2015-05-19 W. A. Coles , B. J. Rickett , J. J. Gao , G. Hobbs , J. P. W. Verbiest

We use VLBA+VLA observations to measure the sizes of the scatter-broadened images of 6 of the most heavily scattered known pulsars: 3 within the Galactic Centre (GC) and 3 elsewhere in the inner Galactic plane. By combining the measured…

Astrophysics of Galaxies · Physics 2017-08-30 J. Dexter , A. Deller , G. C. Bower , P. Demorest , M. Kramer , B. W. Stappers , A. G. Lyne , M. Kerr , L. G. Spitler , D. Psaltis , M. Johnson , R. Narayan

Fast radio bursts (FRBs) have been identified as extragalactic sources which can make a probe of turbulence in the intergalactic medium (IGM) and their host galaxies. To account for the observed millisecond pulses caused by scatter…

High Energy Astrophysical Phenomena · Physics 2016-12-14 Siyao Xu , Bing Zhang

The scattering of electromagnetic radiation by the particle gyrating in an external magnetic field is considered. Particular attention is paid to the low-frequency case, when the frequencies of incident radiation are much less than the…

Astrophysics · Physics 2009-11-13 S. A. Petrova

Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for revisions in the picture of cosmic ray transport. In this paper we use recently obtained scaling laws for MHD modes to obtain the scattering frequency for…

Astrophysics · Physics 2007-05-23 Huirong Yan , A. Lazarian

To date, the search for radio technosignatures has focused on sky location as a primary discriminant between technosignature candidates and anthropogenic radio frequency interference (RFI). In this work, we investigate the possibility of…

Instrumentation and Methods for Astrophysics · Physics 2023-07-19 Bryan Brzycki , Andrew P. V. Siemion , Imke de Pater , James M. Cordes , Vishal Gajjar , Brian Lacki , Sofia Sheikh

Cosmic rays scatter off magnetic irregularities (Alfven waves) with which they are resonant, that is waves of wavelength comparable to their gyroradii. These waves may be generated either by the cosmic rays themselves, if they stream faster…

Astrophysics · Physics 2009-11-10 Alison J. Farmer , Peter Goldreich

Turbulence is a vital part of the interstellar medium (ISM) of galaxies, contributing significantly to galaxy energy budgets and acting as a regulator of star formation. Despite this, little is understood about ISM turbulence empirically.…

Astrophysics of Galaxies · Physics 2021-07-26 Dana Simard , Vikram Ravi

Radio waves propagating through the interstellar medium are influenced by variations in plasma density. For spatially localised plasma structures along the line of sight, time-delay Doppler analyses of pulsars often reveal scintillation…

High Energy Astrophysical Phenomena · Physics 2026-05-15 Tobias Kramer

Radio continuum surveys have, in the past, been of restricted use in cosmology. Most studies have concentrated on cross-correlations with the cosmic microwave background to detect the integrated Sachs-Wolfe effect, due to the large sky…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-19 Matt J. Jarvis , David Bacon , Chris Blake , Michael L. Brown , Sam N. Lindsay , Alvise Raccanelli , Mario Santos , Dominik Schwarz

Recent studies suggest that when magnetohydrodynamic (MHD) turbulence is excited by stirring a plasma at large scales, the cascade of energy from large to small scales is anisotropic, in the sense that small-scale fluctuations satisfy the…

Astrophysics · Physics 2021-04-28 Benjamin D. G. Chandran

Coherent wave propagation in disordered media gives rise to many fascinating phenomena as diverse as universal conductance fluctuations in mesoscopic metals and speckle patterns in light scattering. Here, the theory of electromagnetic wave…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Aris L. Moustakas , Harold U. Baranger , Leon Balents , Anirvan M. Sengupta , Steven H. Simon

Compact radio sources such as pulsars and FRBs undergo scintillation in the interstellar medium (ISM) when scattered images interfere at the observer. ``Scintillometry'' refers to the range of techniques to extract astrometric information…

High Energy Astrophysical Phenomena · Physics 2026-01-30 Dylan L. Jow , Delon Shen

Interplanetary Scintillation (IPS) induces intensity fluctuations in small angular size astronomical radio sources via the distortive effects of spatially and temporally varying electron density associated with outflows from the Sun. These…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-30 Cathryn M. Trott , Steven J. Tingay

Gravitational waves are messengers carrying valuable information about their sources. For sources at cosmological distances, the waves will contain also the imprint left by the intervening matter. The situation is in close analogy with…

General Relativity and Quantum Cosmology · Physics 2015-05-13 Pablo Laguna , Shane L. Larson , David Spergel , Nicolas Yunes