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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…

Pulsar scintillation allows a glimpse into small-scale plasma structures in the interstellar medium, if we can infer their properties from the scintillation pattern. With Very Long Baseline Interferometry and working in delay-delay rate…

Instrumentation and Methods for Astrophysics · Physics 2019-08-07 Dana Simard , Ue-Li Pen , Visweshwar Ram Marthi , Walter Brisken

We have observed the relativistic binary pulsar PSR J1141$-$6545 over a period of $\sim$6 years using the Parkes 64 m radio telescope, with a focus on modelling the diffractive intensity scintillations to improve the accuracy of the…

High Energy Astrophysical Phenomena · Physics 2019-03-20 D. J. Reardon , W. A. Coles , G. Hobbs , S. Ord , M. Kerr , M. Bailes , N. D. R. Bhat , V. Venkatraman Krishnan

We studied the turbulence spectrum of the local interstellar plasma in the direction of PSR J0437-4715, on the basis of our observations and those reported earlier by others. We combine these data to form a structure function for the…

Astrophysics · Physics 2009-11-11 T. V. Smirnova , C. R. Gwinn , V. I. Shishov

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

Compact radio sources sometimes exhibit intervals of large, rapid changes in their flux-density, due to lensing by interstellar plasma crossing the line-of-sight. A novel survey program has made it possible to discover these "Extreme…

Instrumentation and Methods for Astrophysics · Physics 2016-02-03 Artem V. Tuntsov , Mark A. Walker , Leon V. E. Koopmans , Keith W. Bannister , Jamie Stevens , Simon Johnston , Cormac Reynolds , Hayley E. Bignall

We report on findings from scintillation analyses using high-cadence observations of eight canonical pulsars with observing baselines ranging from one to three years. We obtain scintillation bandwidth and timescale measurements for all…

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…

We propose a new method to detect off-pulse (unpulsed and/or continuous) emission from pulsars, using the intensity modulations associated with interstellar scintillation. Our technique involves obtaining the dynamic spectra, separately for…

High Energy Astrophysical Phenomena · Physics 2018-05-23 Kumar Ravi , Avinash A. Deshpande

Weak interstellar scintillations of pulsar B0809+74 were observed at two epochs using a 30m EISCAT antenna at 933 MHz. These have been used to constrain the spectrum, the distribution and the transverse velocity of the scattering plasma…

Astrophysics · Physics 2015-06-24 Barney Rickett , Bill Coles , Jussi Markkanen

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

Observations of radio signals from distant pulsars provide a valuable tool for investigation of interstellar turbulence. The time-shapes of the signals are the result of pulse broadening by the fluctuating electron density in the…

Astrophysics · Physics 2007-05-23 Stanislav Boldyrev , Carl R. Gwinn

To obtain the most accurate pulse arrival times from radio pulsars, it is necessary to correct or mitigate the effects of the propagation of radio waves through the warm and ionised interstellar medium. We examine both the strength of…

Instrumentation and Methods for Astrophysics · Physics 2016-11-15 R. M. Shannon , J. M. Cordes

We calculate detailed modification of pulses from a pulsar arising from the effects of phase transition induced density fluctuations on the pulsar moment of inertia. We represent general statistical density fluctuations using a simple model…

High Energy Astrophysical Phenomena · Physics 2022-04-27 Partha Bagchi , Biswanath Layek , Anjishnu Sarkar , Ajit M. Srivastava

We report long-term scintillation observations of 18 pulsars in the DM range 3-35 pc cm^{-3} carried out during 1993-1995 using the Ooty Radio Telescope at 327 MHz. These observations were made with the aim of studying refractive effects in…

Astrophysics · Physics 2009-10-31 N. D. Ramesh Bhat , A. Pramesh Rao , Yashwant Gupta

Recent radio surveys have revealed pulsars with dispersion and scattering delays induced by ionized gas that are larger than the rest of the observed pulsar population, in some cases with electron column densities (or dispersion measures;…

Astrophysics of Galaxies · Physics 2024-08-05 S. K. Ocker , L. D. Anderson , T. J. W. Lazio , J. M. Cordes , V. Ravi

Annual variations of interstellar scintillation can be modelled to constrain parameters of the ionized interstellar medium. If a pulsar is in a binary system, then investigating the orbital parameters is possible through analysis of the…

We present 154 MHz Murchison Widefield Array imaging observations and variability information for a sample of pulsars. Over the declination range $-80^{\circ} < {\delta} < 10^{\circ}$ we detect 17 known pulsars with mean flux density…

Context. The spatially coherent multipath propagation of pulsar radiation leads to a temporal and spectral interference patterns called scintillation. It is caused by density variations in the ionized interstellar medium, which often take…

High Energy Astrophysical Phenomena · Physics 2026-05-15 Tim Sprenger , Xun Shi , Olaf Wucknitz , Robert A. Main