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Related papers: Faint Scattering Around Pulsars: Probing the Inter…

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We present the results from an Australian Square Kilometre Array Pathfinder search for radio variables on timescales of hours. We conducted an untargeted search over a 30 deg$^2$ field, with multiple 10-hour observations separated by days…

High-resolution imaging observations from the Hinode spacecraft in the CaII H line are employed to study the dynamics of the chromosphere above a sunspot. We find that umbral flashes and other brightenings produced by the oscillation are…

Astrophysics · Physics 2011-02-11 H. Socas-Navarro , S. W. McIntosh , R. Centeno , A. G. de Wijn , B. W. Lites

We calculate the scattering of X-rays by interstellar dust, for a dust model that reproduces the observed wavelength-dependent extinction and polarization of starlight. On interstellar sightlines that produce appreciable starlight…

Astrophysics · Physics 2008-11-26 B. T. Draine , Khosrow Allaf-Akbari

PKS 1257-326 is a quasar showing extremely unusual, rapid interstellar scintillation (ISS), which has persisted for at least a decade. Simultaneous observations with the VLA and ATCA, combined with ATCA monitoring over several years, have…

Interstellar scintillation analysis of pulsars allows us to probe the small-scale distribution and inhomogeneities of the ionized interstellar medium. Our priority is to present the data set and the basic measurements of scintillation…

We present a robust approach to incorporating models for the time-variable broadening of the pulse profile due to scattering in the ionized interstellar medium into profile-domain pulsar timing analysis. We use this approach to…

Instrumentation and Methods for Astrophysics · Physics 2017-04-12 L. Lentati , M. Kerr , S. Dai , R. M. Shannon , G. Hobbs , S. Oslowski

We present multi-wavelength scatter broadening observations of 47 pulsars, made with the Giant Metre-wave Radio Telescope (GMRT), Ooty Radio Telescope (ORT) and Long Wavelength Array (LWA). The GMRT observations have been made in the phased…

High Energy Astrophysical Phenomena · Physics 2017-09-13 M. A. Krishnakumar , Bhal Chandra Joshi , P. K. Manoharan

Radio wave scattering can cause severe reductions in detection sensitivity for surveys of Galactic and extragalactic fast ($\sim$ms duration) transients. While Galactic sources like pulsars undergo scattering in the Milky Way interstellar…

Astrophysics of Galaxies · Physics 2022-08-03 S. K. Ocker , J. M. Cordes , S. Chatterjee , M. R. Gorsuch

Our analysis of archival VLBI data of PSR 0834+06 revealed that its scintillation properties can be precisely modelled using the inclined sheet model (Pen & Levin 2014), resulting in two distinct lens planes. These data strongly favour the…

Solar and Stellar Astrophysics · Physics 2016-02-17 Siqi Liu , Ue-Li Pen , J-P Macquart , Walter Brisken , Adam Deller

Scintillation of pulsar radio signals caused by the interstellar medium can in principle be used for interstellar interferometry. Changes of the dynamic spectra as a function of pulsar longitude were in the past interpreted as having…

We conducted radio interferometric observations of six pulsars at 610 MHz using the Giant Metrewave Radio Telescope (GMRT). All these objects were claimed or suspected to be the gigahertz-peaked spectra (GPS) pulsars. For a half of the…

High Energy Astrophysical Phenomena · Physics 2015-06-24 M. Dembska , R. Basu , J. Kijak , W. Lewandowski

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

The scintillation of pulsars reveals small-scale structure of the interstellar medium. A powerful technique for characterizing the scintillating structures (screens) combines analysis of scintillation arcs and very long baseline…

High Energy Astrophysical Phenomena · Physics 2025-10-21 Ashley M. Stock , Fardin Syed , Marten H. van Kerkwijk , Rebecca Lin , Franz Kirsten , Ue-Li Pen

We use VLBI imaging of the interstellar scattering speckle pattern associated with the pulsar PSR 0834+06 to measure the astrometric motion of its emission. The ~ 5AU interstellar baselines, provided by interference between speckles…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Ue-Li Pen , J. P. Macquart , Adam Deller , Walter Brisken

The pulsed radio emission from the Galactic Center (GC) magnetar SGR J1745-29 probes the turbulent, magnetized plasma of the GC hyperstrong scattering screen through both angular and temporal broadening. We present the first measurements of…

In this work we adopted a CLEAN-based method to determine the scatter time, $\tau$, from archived pulsar profiles under both the thin screen and uniform medium scattering models and to calculate the scatter time frequency scale index…

High Energy Astrophysical Phenomena · Physics 2017-01-23 Jr-Wei Tsai , John H. Simonetti , Michael Kavic

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 report on observations of PSR B1508+55's scintillation at the Effelsberg 100-m telescope spanning from early 2020 to early 2022. In the autumn of 2020, close to the time the pulsar was predicted to cross echoes in its pulse profile, a…

High Energy Astrophysical Phenomena · Physics 2023-02-06 Tim Sprenger , Robert Main , Olaf Wucknitz , Geetam Mall , Jason Wu

Gravitational scattering events, in which the path of an interstellar object is deflected by a pulsar or the solar system, give rise to reflex motion which can potentially be detected using pulsar timing. We determine the form of the timing…

High Energy Astrophysical Phenomena · Physics 2020-02-12 Ross J. Jennings , James M. Cordes , Shami Chatterjee

We have monitored a large sample of millisecond pulsars using the 100-m Effelsberg radio telescope in order to compare their radio emission properties to the slowly rotating population. With some notable exceptions, our findings suggest…