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Related papers: Interplanetary Scintillation studies with the Murc…

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We report the first astrophysical application of the technique of wide-field Interplanetary Scintillation (IPS) with the Murchison Widefield Array (MWA). This powerful technique allows us to identify and measure sub-arcsecond compact…

High Energy Astrophysical Phenomena · Physics 2018-01-10 R. Chhetri , J. Morgan , R. D. Ekers , J-P Macquart , E. M. Sadler , M. Giroletti , J. R. Callingham , S. J. Tingay

Around 10% of bright low-frequency radio sources observed with the Murchison Widefield Array (MWA) show strong Interplanetary Scintillation (IPS) on timescales of a few seconds, implying that almost all their low-frequency radio emission…

Astrophysics of Galaxies · Physics 2018-11-28 Elaine M. Sadler , Rajan Chhetri , John Morgan , Elizabeth K. Mahony , Thomas H. Jarrett , Steven Tingay

We present a catalogue of over 7000 sources from the GLEAM survey which have significant structure on sub-arcsecond scales at 162MHz. The compact nature of these sources was detected and quantified via their Interplanetary Scintillation…

Instrumentation and Methods for Astrophysics · Physics 2023-01-04 John Morgan , Rajan Chhetri , Ron Ekers

We present the first dedicated observations of Interplanetary Scintillation (IPS) with the Murchison Widefield Array (MWA). We have developed a synthesis imaging technique, tailored to the properties of modern "large-N" low-frequency radio…

Instrumentation and Methods for Astrophysics · Physics 2017-09-12 J . S. Morgan , J-P. Macquart , R. Ekers , R. Chhetri , M. Tokumaru , P. K. Manoharan , S. Tremblay , M. M. Bisi , B. V. Jackson

Interplanetary scintillation (IPS) provides an approach for identifying the presence of sub-arcsec structures in radio sources, and very long baseline interferometry (VLBI) technique can help verify whether the IPS sources have fine…

Astrophysics of Galaxies · Physics 2021-10-27 Sumit Jaiswal , Tao An , Ailing Wang , Steven Tingay

The search for compact components of strong ($S_{int} \ge 5$ Jy at 102.5 MHz) discrete radio sources from the Pushchino catalogue was carried out using the method of interplanetary scintillation. A total of 3620 sources were examined, and…

High Energy Astrophysical Phenomena · Physics 2022-07-18 S. A. Tyul'bashev , I. V. Chashei , I. A. Subaev , M. A. Kitaeva

We describe the parameters of a low-frequency all-sky survey of compact radio sources using Interplanetary Scintillation (IPS), undertaken with the Murchison Widefield Array (MWA). While this survey gives important complementary information…

Astrophysics of Galaxies · Physics 2019-02-08 J. S. Morgan , J-P. Macquart , R. Chhetri , R. D. Ekers , S. J. Tingay , E. M. Sadler

We determine the small-scale structure for a large sample of Compact Steep Spectrum (CSS) and Gigahertz Peaked Spectrum (GPS) sources and a sample of larger radio sources at 327 MHz using the technique of Inter-Planetary Scintillation (IPS)…

Astrophysics · Physics 2007-05-23 S. Jeyakumar , D. J. Saikia , A. Pramesh Rao , V. Balasubramanian

From 1979--1996 the Green Bank Interferometer was used by the Naval Research Laboratory to monitor the flux density from 146 compact radio sources at frequencies near 2 and 8 GHz. We filter the ``light curves'' to separate intrinsic…

Astrophysics · Physics 2009-11-11 B. Rickett , T. J. W. Lazio , F. D. Ghigo

We present observations of high-amplitude rapid (2 s) variability toward two bright, compact extragalactic radio sources out of several hundred of the brightest radio sources in one of the 30x30 deg MWA Epoch of Reionization fields using…

The 4.9 GHz Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey detected a drop in Interstellar Scintillation (ISS) for sources at redshifts z > 2, indicating an apparent increase in angular diameter or a decrease in flux…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-09 J. Y Koay , J. -P. Macquart , B. J. Rickett , H. E. Bignall , J. E. J. Lovell , C. Reynolds , D. L. Jauncey , T. Pursimo , L. Kedziora-Chudczer , R. Ojha

Interplanetary scintillation observations of 48 of the 55 Augusto et al. (1998) flat spectrum radio sources were carried out at 111 MHz using the interplanetary scintillation method on the Large Phased Array (LPA) in Russia. Due to the…

Astrophysics · Physics 2009-11-11 S. A. Tyul'bashev , A. Pedro

We present a sample of 1,483 sources that display spectral peaks between 72 MHz and 1.4 GHz, selected from the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey. The GLEAM survey is the widest fractional bandwidth…

We report on the variability of 443 flat spectrum, compact radio sources monitored using the VLA for 3 days in 4 epochs at ~ 4 month intervals at 5 GHz as part of the Micro-Arcsecond Scintillation-Induced Variability (MASIV) survey. Over…

Compact steep-spectrum (CSS) and peaked spectrum (PS) radio sources are compact, powerful radio sources. The multi-frequency observational properties and current theories are reviewed with emphasis on developments since the earlier review…

Astrophysics of Galaxies · Physics 2021-04-07 Christopher P. O'Dea , D. J. Saikia

Comparing the asymmetry coefficients and scintillation indices for observed time variations of the intensity of the radiation of extragalactic sources and the predictions of theoretical models is a good test of the nature of the observed…

Astrophysics · Physics 2009-11-11 V. I. Shishov , T. V. Smirnova , S. A. Tyul'bashev

According to a generally accepted paradigm, small intrinsic sizes of Compact Steep Spectrum (CSS) radio sources are a direct consequence of their youth, but in later stages of their evolution they are believed to become large-scale sources.…

Astrophysics · Physics 2009-11-13 Andrzej Marecki , Magdalena Kunert-Bajraszewska , Ralph E. Spencer

We demostrate that the measurement of fluctuations of polarization due to the galactic interstellar scintillations may be used to study the structure of the radiation field at compact radio sources. We develop a mathematical formalism and…

Astrophysics · Physics 2009-10-31 Mikhail V. Medvedev

The shape of the curves defined by the counts of radio sources per unit area as a function of their flux density was one of the earliest cosmological probes. Radio source counts continue to be an area of interest, used to study the relative…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Ian Heywood , Matt J. Jarvis , James J. Condon
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