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We present the results of a coordinated campaign conducted with the Murchison Widefield Array (MWA) to shadow Fast Radio Bursts (FRBs) detected by the Australian Square Kilometre Array Pathfinder (ASKAP) at 1.4 GHz, which resulted in…

The Murchison Widefield Array (MWA) team has derived new upper limits on the spherically averaged power spectrum of the 21-cm signal at six redshifts in the range $z \approx 6.5-8.7$. We use these upper limits and a Bayesian inference…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-24 Raghunath Ghara , Sambit K. Giri , Benedetta Ciardi , Garrelt Mellema , Saleem Zaroubi

This paper presents a framework to compute the receiver noise temperature (Trcv) of two low-frequency radio telescopes, the Murchison Widefield Array (MWA) and the Engineering Development Array (EDA). The MWA was selected because it is the…

Instrumentation and Methods for Astrophysics · Physics 2020-03-23 Daniel C. X. Ung , Marcin Sokolowski , Adrian T. Sutinjo , David B. Davidson

The Epoch of Reionisation (EoR) is the period within which the neutral universe transitioned to an ionised one. This period remains unobserved using low-frequency radio interferometers which target the 21 cm signal of neutral hydrogen…

Instrumentation and Methods for Astrophysics · Physics 2021-07-01 J. Kariuki Chege , C. H. Jordan , C. Lynch , J. L. B. Line , C. M. Trott

We present the first observational limits on the predicted synchrotron signals from particle Dark Matter annihilation models in dwarf spheroidal galaxies at radio frequencies below 1 GHz. We use a combination of survey data from the…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Arpan Kar , Sourav Mitra , Biswarup Mukhopadhyaya , Tirthankar Roy Choudhury , Steven Tingay

We describe the design and performance of the Engineering Development Array (EDA), which is a low frequency radio telescope comprising 256 dual-polarisation dipole antennas working as a phased-array. The EDA was conceived of, developed, and…

We present a description of the Dragonfly Wide Field Survey (DWFS), a deep photometric survey of a wide area of sky. The DWFS covers 330 $\mathrm{deg}^2$ in the equatorial GAMA fields and the Stripe 82 fields in the SDSS $g$ and $r$ bands.…

Using the final 128 antenna locations of the Murchison Widefield Array (MWA), we calculate its sensitivity to the Epoch of Reionization (EoR) power spectrum of red- shifted 21 cm emission for a fiducial model and provide the tools to…

We apply two methods to estimate the 21~cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum…

Galaxy clusters have been found to host a range of diffuse, non-thermal emission components, generally with steep, power law spectra. In this work we report on the detection and follow-up of radio halos, relics, remnant radio galaxies, and…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-20 S. W. Duchesne , M. Johnston-Hollitt , I. Bartalucci

We search data from the GLEAM-X survey, obtained with the Murchison Widefield Array (MWA) in 2020, for the presence of radio frequency interference from distant Earth-orbiting satellites, in the form of unintended emissions similar to those…

Instrumentation and Methods for Astrophysics · Physics 2025-12-09 S. J. Tingay , N. Hurley-Walker , K. Ross , T. J. Galvin , J. Morgan , B. Venville

Several experimental efforts are underway to measure the power spectrum of 21cm fluctuations from the Epoch of Reionization (EoR) using low-frequency radio interferometers. Experiments like the Hydrogen Epoch of Reionization Array (HERA)…

Instrumentation and Methods for Astrophysics · Physics 2019-06-19 Adam E. Lanman , Jonathan C. Pober

The Murchison Widefield Array (MWA), located in Western Australia, is one of the low-frequency precursors of the international Square Kilometre Array (SKA) project. In addition to pursuing its own ambitious science program, it is also a…

We have previously presented the results of a 325 MHz radio survey of M31, conducted with the A-configuration of the Very Large Array. In this survey, a total of 405 radio sources between <6" and 170" in extent were mapped with a resolution…

Astrophysics · Physics 2009-11-11 Joseph D. Gelfand , T. J. W. Lazio , B. M. Gaensler

We present here the results of a 325 MHz radio survey of M31, conducted with the A-configuration of the Very Large Array. The survey covered an area of 7.6 deg$^2$, and a total of 405 radio sources between $\la$6\arcsec and 170\arcsec in…

Astrophysics · Physics 2009-11-10 Joseph D. Gelfand , T. Joseph W. Lazio , B. M. Gaensler

We present the second data release for the GaLactic and Extragalactic All-sky Murchison Widefield Array eXtended (GLEAM-X) survey. This data release is an area of 12,892-deg^2 around the South Galactic Pole region covering 20h 40m <= RA <=…

The radio interferometric closure phases can be a valuable tool for studying cosmological {H\scriptsize{I}}~from the early Universe. Closure phases have the advantage of being immune to element-based gains and associated calibration errors.…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-05 Himanshu Tiwari , Nithyanandan Thyagarajan , Cathryn M. Trott , Benjamin McKinley

We present a method for subtracting point sources from interferometric radio images via forward modeling of the instrument response and involving an algebraic nonlinear minimization. The method is applied to simulated maps of the Murchison…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Bernardi , D. A. Mitchell , S. M. Ord , L. J. Greenhill , B. Pindor , R. B. Wayth , J. S. B. Wyithe

We present techniques for bridging the gap between idealized inverse covariance weighted quadratic estimation of 21 cm power spectra and the real-world challenges presented universally by interferometric observation. By carefully evaluating…

We have conducted a comprehensive comparison of interplanetary scintillation (IPS) observations taken by the Murchison Widefield Array (MWA) with several heliospheric transient event catalogues, over a time period of 7 months during solar…

Solar and Stellar Astrophysics · Physics 2025-11-11 A. Waszewski , J. S. Morgan , M. C. M. Cheung , R. Ekers , E. Samara , S. Majumdar , R. Chhetri , N. D. R. Bhat , M. Johnston-Hollitt