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Related papers: Scattering analysis of LOFAR pulsar observations

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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…

We present temporal scattering measurements of single pulses and average profiles of PSR J1745--2900, a magnetar recently discovered only 3 arcsec away from Sagittarius A* (Sgr A*), from 1.2 - 18.95 GHz using the Effelsberg 100-m Radio…

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…

Nonlinear Compton scattering is calculated for the collision of an electron with a plane wave pulse. A mid infra-red (IR) peak arises in the photon spectrum due to long-range interference associated with the pulse envelope. The case of a…

High Energy Physics - Phenomenology · Physics 2021-03-03 B. King

The effect of interplanetary plasma on pulsed pulsar radiation passing through is considered. The pulses of two rotating radio transients (J0609+16, J1132+25) and a pulsar (B0320+39) detected on the Large Phased Array (Pushchino…

High Energy Astrophysical Phenomena · Physics 2023-05-24 S. A. Tyul'bashev , I. V. Chashei , M. A. Kitaeva

Giant pulses from Crab pulsar were observed together with Radioastron space radiotelescope, Global EVN radio telescopes and Kvazar-KVO VLBI stations to study the scattering effects in the ISM. Five observing sessions were conducted at 18 cm…

Solar and Stellar Astrophysics · Physics 2015-05-06 Alexey Rudnitskiy , Mikhail Popov , Vladimir Soglasnov

We report on the multi-frequency timing observations of 21 pulsars discovered in the LOFAR Tied-Array All-Sky Survey (LOTAAS). The timing data were taken at central frequencies of 149 MHz (LOFAR) as well as 334 and 1532 MHz (Lovell…

We are using the LOw-Frequency ARray (LOFAR) to perform the LOFAR Tied-Array All-Sky (LOTAAS) survey for pulsars and fast transients. Here we present the astrometric and rotational parameters of 20 pulsars discovered as part of LOTAAS.…

We present initial pulsar results from the first station of the Long Wavelength Array (LWA1) obtained during the commissioning period of LWA1 and early science results. We present detections of periodic emission from 44 previously known…

Instrumentation and Methods for Astrophysics · Physics 2015-08-06 K. Stovall , P. S. Ray , J. Blythe , J. Dowell , T. Eftekhari , A. Garcia , T. J. W. Lazio , M. McCrackan , F. K. Schinzel , G. B. Taylor

Since 2013 round-the-clock monitoring of the sky is carried out simultaneously in 96 space beams using the high-sensitivity radio telescope of LPA (Large Phased Array) at the frequency 110.25 MHz. These observations are made under the…

High Energy Astrophysical Phenomena · Physics 2018-08-15 V. M. Malofeev , S. A. Tyul'bashev

Many models for the pulsar radio and $\gamma$-ray emissions have been developed. The tests for these models using observational data are very important. Tests for the pulsar radio emission models using frequency-altitude relation are…

Astrophysics · Physics 2008-11-26 G. J. Qiao , K. J. Lee , H. G. Wang , R. X. Xu , B. Zhang

We present broadband ionospheric scintillation observations of highly defined symmetric quasi-periodic oscillations (QPO: Maruyama 1991) caused by plasma structures in the midlatitude ionosphere using the LOw Frequency ARray (LOFAR: van…

Space Physics · Physics 2023-12-08 Hannah Trigg , Gareth Dorrian , Ben Boyde , Alan Wood , Richard Fallows , Maaijke Mevius

We analyze plasma dispersion and scattering of fast radio bursts (FRBs) to identify the dominant locations of free electrons along their lines of sight and thus constrain the distances of the burst sources themselves. We establish the…

High Energy Astrophysical Phenomena · Physics 2016-05-20 J. M. Cordes , R. S. Wharton , L. G. Spitler , S. Chatterjee , I. Wasserman

Motivated by recent results on the location of the radio emission in pulsar magnetospheres, we have developed a model which can account for the large diversity found in the average profile shapes of pulsars. At the centre of our model lies…

Astrophysics · Physics 2009-11-13 A. Karastergiou , S. Johnston

A new method for separating intensity variations of a source's radio emission having various physical natures is proposed. The method is based on a joint analysis of the structure function of the intensity variations and the asymmetry…

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

We have developed a method to compute the possible distribution of radio emission regions in a typical pulsar magnetosphere, taking into account the viewing geometry and rotational effects of the neutron star. Our method can estimate the…

Astrophysics of Galaxies · Physics 2015-05-18 R. M. C. Thomas , Y. Gupta , R. T. Gangadhara

In this paper we present recent Low Frequency Array (LOFAR) observations of the pulsar J1740+1000. We confirm that its spectrum has a turnover at 260 MHz, which is unusual for a typical pulsar. We argue that in this case interferometric…

High Energy Astrophysical Phenomena · Physics 2021-04-02 K. Rozko , J. Kijak , K. Chyzy , W. Lewandowski , T. Shimwell , S. S. Sridhar , M. Curylo , A. Krankowski , L. Blaszkiewicz

The Parkes telescope has been monitoring 286 radio pulsars approximately monthly since 2007 at an observing frequency of 1.4 GHz. The wide dispersion measure (DM) range of the pulsar sample and the uniformity of the observing procedure make…

High Energy Astrophysical Phenomena · Physics 2021-01-06 H. Kumamoto , S. Dai , S. Johnston , M. Kerr , R. M. Shannon , P. Weltevrede , C. Sobey , R. N. Manchester , G. Hobbs , K. Takahashi

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

Density fluctuations in the ionised interstellar medium have a profound effect on radio pulsar observations, through angular scattering, intensity scintillations, and small changes in time delays from dispersion. Here we show that it is…

High Energy Astrophysical Phenomena · Physics 2023-04-12 Daniel J. Reardon , William A. Coles