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Related papers: Imaging pulsar echoes at low frequencies

200 papers

Observations of pulsar scintillation are among the few astrophysical probes of very small-scale ($\lesssim$ au) phenomena in the interstellar medium (ISM). In particular, characterization of scintillation arcs, including their curvature and…

High Energy Astrophysical Phenomena · Physics 2023-11-28 S. K. Ocker , J. M. Cordes , S. Chatterjee , D. R. Stinebring , T. Dolch , V. Pelgrims , J. W. McKee , C. Giannakopoulos , D. J. Reardon

Scintillation arcs have become a powerful tool for exploring scattering in the ionized interstellar medium. There is accumulating evidence that the scattering from many pulsars is extremely anisotropic resulting in highly elongated, linear…

Astrophysics of Galaxies · Physics 2019-01-11 Dan R. Stinebring , Barney J. Rickett , Stella Koch Ocker

Light travel time changes due to gravitational waves may be detected within the next decade through precision timing of millisecond pulsars. Removal of frequency-dependent interstellar medium (ISM) delays due to dispersion and scattering is…

Instrumentation and Methods for Astrophysics · Physics 2015-12-16 Nipuni Palliyaguru , Daniel Stinebring , Maura McLaughlin , Paul Demorest , Glenn Jones

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 present multi-frequency scatter broadening evolution of 29 pulsars observed with the LOw Frequency ARray (LOFAR) and Long Wavelength Array (LWA). We conducted new observations using LOFAR Low Band Antennae (LBA) as well as utilized the…

High Energy Astrophysical Phenomena · Physics 2019-06-26 M. A. Krishnakumar , Yogesh Maan , Bhal Chandra Joshi , P. K. Manoharan

The magnetized induced Compton scattering off the particles of the ultrarelativistic electron-positron plasma of pulsar is considered. The main attention is paid to the transverse regime of the scattering, which holds in a moderately strong…

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

Pulsar timing at low frequencies offers a powerful tool for studying the interstellar medium. Additionally, pulsar observations in the ecliptic enables us to study the effects of the solar wind which becomes much more prominent at low radio…

High Energy Astrophysical Phenomena · Physics 2025-06-25 S. C. Susarla , O. A. Johnson , D. J. McKenna , E. F. Keane , P. J. McCauley , J. P. W. Verbiest , C. Tiburzi , A. Golden

In long-baseline interferometry, bandwidth smearing of an extended source occurs at finite bandwidth when its different components produce interference packets that only partially overlap. In this case, traditional model fitting or image…

Instrumentation and Methods for Astrophysics · Physics 2013-08-07 Régis Lachaume , Jean-Philippe Berger

Light scattering in inhomogeneous media induces wavefront distortions which pose an inherent limitation in many optical applications. Examples range from microscopy and nanosurgery to astronomy. In recent years, ongoing efforts have made…

Optics · Physics 2015-05-20 Ori Katz , Yaron Bromberg , Eran Small , Yaron Silberberg

Refraction of pulsar radiation by electron density irregularities in the interstellar medium sometimes produces multiple imaging of pulsars which can lead to periodic oscillations of intensity in pulsar dynamic spectra records. Such events…

Astrophysics · Physics 2007-05-23 Yashwant Gupta , N. D. Ramesh Bhat , A. Pramesh Rao

Low frequency radio waves, while challenging to observe, are a rich source of information about pulsars. The LOw Frequency ARray (LOFAR) is a new radio interferometer operating in the lowest 4 octaves of the ionospheric "radio window":…

Just as turbulence in the Earth's atmosphere can severely limit the angular resolution of optical telescopes, turbulence in the ionized interstellar medium fundamentally limits the resolution of radio telescopes. We present a scattering…

Instrumentation and Methods for Astrophysics · Physics 2016-12-14 Michael D. Johnson

The low-frequency profiles of some pulsars manifest temporal broadening due to scattering, usually accompanied by flat polarization position angle (PA) curves. Assuming that the scattering works on the 4 Stokes parameters in the same way,…

Astrophysics · Physics 2008-11-26 X. H. Li , J. L. Han

Radio pulsars, as highly coherent point sources, serve as powerful probes of the ionized interstellar medium (IISM). Pulsar scintillation observations have revealed inverted arclets on the secondary spectrum, indicating quasilinearly…

Astrophysics of Galaxies · Physics 2026-04-14 Zhu Xu , Xun Shi

In this paper, we report our investigation of pulsar scintillation phenomena by monitoring PSR B0355$+$54 at 2.25 GHz for three successive months using \emph{Kunming 40-m radio telescope}. We have measured the dynamic spectrum, the…

We report on an effort to extract and monitor interstellar scintillation parameters in regular timing observations collected for the NANOGrav pulsar timing array. Scattering delays are measured by creating dynamic spectra for each pulsar…

We present the first large sample of scintillation arcs in millisecond pulsars, analysing 12 sources observed with the Large European Array for Pulsars (LEAP), and the Effelsberg 100\,m telescope. We estimate the delays from multipath…

Radio pulsar signals are significantly perturbed by their propagation through the ionized interstellar medium. In addition to the frequency-dependent pulse times of arrival due to dispersion, pulse shapes are also distorted and shifted,…