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Related papers: Analysis of Scattering from Archival Pulsar Data u…

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We have measured variations in scattering time scales in the Crab Pulsar over a 30-year period, using observations made at 610 MHz with the 42-ft telescope at Jodrell Bank Observatory. Over more recent years, where regular Lovell Telescope…

High Energy Astrophysical Phenomena · Physics 2018-07-18 J. W. McKee , A. G. Lyne , B. W. Stappers , C. G. Bassa , C. A. Jordan

We present the measurements of scatter broadening time-scales ($\tau_{sc}$) for 124 pulsars at 327 MHz, using the upgraded Ooty Radio Telescope (ORT). These pulsars lie in the dispersion measure range of 37 $-$ 503 pc cm$^{-3}$ and…

High Energy Astrophysical Phenomena · Physics 2017-06-20 M. A. Krishnakumar , Dipanjan Mitra , Arun Naidu , Bhal Chandra Joshi , P. K. Manoharan

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

We report the discovery and timing of two pulsars from a sample of four circularly polarized sources identified in radio continuum images taken as part of the Australian SKA Pathfinder (ASKAP) Variables and Slow Transients (VAST) survey.…

High Energy Astrophysical Phenomena · Physics 2026-03-17 Rahul Sengar , David L. Kaplan , Emil Lenc , Akash Anumarlapudi , Natasha Hurley-Walker , Ziteng Wang , Laura Driessen , Dougal Dobie , Tara Murphy

We show the results of our analysis of the pulse broadening phenomenon in 25 pulsars at several frequencies using the data gathered with GMRT and Effelsberg radiotelescopes. Twenty two of these pulsars were not studied in that regard before…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Wojciech Lewandowski , Marta Dembska , Jaroslaw Kijak , Magdalena Kowalinska

Multipath propagation in the interstellar medium distorts radio pulses, an effect predominant for distant pulsars observed at low frequencies. Typically, broadened pulses are analyzed to determine the amount of propagation-induced pulse…

Astrophysics · Physics 2009-11-07 N. D. R. Bhat , J. M. Cordes , S. Chatterjee

Due to the inhomogeneity of electron number density, radio waves emitted by pulsars undergo scattering as they pass through the interstellar medium (ISM). However, a connection between large-scale pulsar scattering data and the structure of…

Astrophysics of Galaxies · Physics 2025-02-14 Qiuyi He , Xun Shi , Guangxing Li

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,…

We present here a method to study the distribution of electron density fluctuations in pulsar directions as well as to estimate pulsar distances. The method, based on a simple two-component model of the scattering medium discussed by Gwinn…

Astrophysics · Physics 2009-10-30 A. A. Deshpande , R. Ramachandran

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 have made high-resolution, high-sensitivity dynamic spectra of a sample of strong pulsars at 430 MHz with the Arecibo radiotelescope. For 4 pulsars we find faint but sharply delineated features in the secondary spectra. These are…

Interstellar scattering causes broadening and distortion to the mean pulse profiles and polarization position angle (PPA) curves, especially to the pulse profiles observed at lower frequency. This paper has implemented a method to recover…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Abdujappar Rusul , Ali Esamdin , Alim Kerim , Dilnur Abdurixit , Hongguang Wang , Xiao-Ping Zheng

We report the discovery of 19 new pulsars identified from archival observations of the Five-hundred-meter Aperture Spherical radio Telescope (FAST) within Galactic latitudes $|b|<5\deg$ and declinations ${\rm Decl.}<-5\deg$. The dataset was…

High Energy Astrophysical Phenomena · Physics 2026-01-06 Shi-Jie Gao , Yi-Xuan Shao , Xiang-Dong Li

Context. Interstellar scintillation (ISS) of pulsar emission can be used both as a probe of the ionised interstellar medium (IISM) and cause corruptions in pulsar timing experiments. Of particular interest are so-called scintillation arcs…

Observations reveal a uniform Kolmogorov turbulence throughout the diffuse ionized interstellar medium (ISM) and supersonic turbulence preferentially located in the Galactic plane. Correspondingly, we consider the Galactic distribution of…

Astrophysics of Galaxies · Physics 2017-01-25 Siyao Xu , Bing Zhang

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

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

High-precision timing of millisecond pulsars (MSPs) over years to decades is a promising technique for direct detection of gravitational waves at nanohertz frequencies. Time-variable, multi-path scattering in the interstellar medium is a…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Anne M. Archibald , Vladislav I. Kondratiev , Jason W. T. Hessels , Daniel R. Stinebring

We report on Westerbork Synthesis Radio Telescope observations of the Crab pulsar at 350 MHz from 2012 November 24 until 2015 June 21. During this period we consistently observe variations in the pulse profile of the Crab. Both variations…

High Energy Astrophysical Phenomena · Physics 2018-12-19 L. N. Driessen , G. H. Janssen , C. G. Bassa , B. W. Stappers , D. R. Stinebring

Interstellar scattering is known to broaden distant objects spatially and temporally. The latter aspect is difficult to analyse, unless the signals carry their own time stamps. Pulsars are so kind to do us this favour. Typically the…

Astrophysics of Galaxies · Physics 2019-04-26 Olaf Wucknitz