A. D. Kapińska

GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey – I. A low-frequency extragalactic catalogue

Using the Murchison Widefield Array (MWA), the low-frequency Square Kilometre Array precursor located in Western Australia, we have completed the GaLactic and Extragalactic All-sky MWA (GLEAM) survey and present the resulting extragalactic catalogue, utilizing the first year of observations. The catalogue covers 24 831 square degrees, over declinations south of +30° and Galactic latitudes outside 10° of the Galactic plane, excluding some areas such as the Magellanic Clouds. It contains 307 455 radio sources with 20 separate flux density measurements across 72–231 MHz, selected from a time- and frequency-integrated image centred at 200 MHz, with a resolution of ≈ 2 arcmin. Over the catalogued region, we estimate that the catalogue is 90 per cent complete at 170 mJy and 50 per cent complete at 55 mJy and large areas are complete at even lower flux density levels. Its reliability is 99.97 per cent above the detection threshold of 5σ, which itself is typically 50 mJy. These observations constitute the widest fractional bandwidth and largest sky area survey at radio frequencies to date and calibrate the low-frequency flux density scale of the southern sky to better than 10 per cent. This paper presents details of the flagging, imaging, mosaicking and source extraction/characterization, as well as estimates of the completeness and reliability. All source measurements and images are available online. 1 This is the first in a series of publications describing the GLEAM survey results.

GLEAM: The GaLactic and Extragalactic All-Sky MWA Survey

© Astronomical Society of Australia 2015; published by Cambridge University Press. This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY 4.0) license, which permits others to distribute, remix, adapt and build upon this work, for commercial use, provided the original work is properly cited. See: http://creativecommons.org/licenses/by/4.0/

LOFAR 150-MHz observations of the Boötes field: catalogue and source counts

We present the first wide area (19 deg(2)), deep (a parts per thousand 120-150 mu Jy beam(-1)), high-resolution (5.6 x 7.4 arcsec) LOFAR High Band Antenna image of the Bootes field made at 130-169 MHz. This image is at least an order of magnitude deeper and 3-5 times higher in angular resolution than previously achieved for this field at low frequencies. The observations and data reduction, which includes full direction-dependent calibration, are described here. We present a radio source catalogue containing 6 276 sources detected over an area of 19 deg(2), with a peak flux density threshold of 5 sigma. As the first thorough test of the facet calibration strategy, introduced by van Weeren et al., we investigate the flux and positional accuracy of the catalogue. We present differential source counts that reach an order of magnitude deeper in flux density than previously achieved at these low frequencies, and show flattening at 150-MHz flux densities below 10 mJy associated with the rise of the low flux density star-forming galaxies and radio-quiet AGN.

The LOFAR Two-metre Sky Survey - I. Survey description and preliminary data release

The LOFAR Two-metre Sky Survey (LoTSS) is a deep 120-168 MHz imaging survey that will eventually cover the entire northern sky. Each of the 3170 pointings will be observed for 8 h, which, at most declinations, is sufficient to produce ~5? resolution images with a sensitivity of ~100 ?Jy/beam and accomplish the main scientific aims of the survey, which are to explore the formation and evolution of massive black holes, galaxies, clusters of galaxies and large-scale structure. Owing to the compact core and long baselines of LOFAR, the images provide excellent sensitivity to both highly extended and compact emission. For legacy value, the data are archived at high spectral and time resolution to facilitate subarcsecond imaging and spectral line studies. In this paper we provide an overview of the LoTSS. We outline the survey strategy, the observational status, the current calibration techniques, a preliminary data release, and the anticipated scientific impact. The preliminary images that we have released were created using a fully automated but direction-independent calibration strategy and are significantly more sensitive than those produced by any existing large-Area low-frequency survey. In excess of 44 000 sources are detected in the images that have a resolution of 25?, typical noise levels of less than 0.5 mJy/beam, and cover an area of over 350 square degrees in the region of the HETDEX Spring Field (right ascension 10h45m00s to 15h30m00s and declination 45°00?00? to 57°00?00?).

The Low-Frequency Environment of the Murchison Widefield Array: Radio-Frequency Interference Analysis and Mitigation

This is the Accepted Manuscript version of the following article: A. R. Offringa, et al., “The low-frequency environment of the Murchison Widefield Array: radio-frequency interference analysis and mitigation”, Publications of the Astronomical Society of Australia, Vol. 32, March 2015. The final published version is available at: https://doi.org/10.1017/pasa.2015.7

Radio Galaxy Zoo: Host galaxies and radio morphologies derived from visual inspection

We present results from the first twelve months of operation of Radio Galaxy Zoo, which upon completion will enable visual inspection of over 170,000 radio sources to determine the host galaxy of the radio emission and the radio morphology. Radio Galaxy Zoo uses

Determining the radio active galactic nuclei contribution to the radio–far-infrared correlation using the black hole Fundamental Plane relation

1.4\,

Ionospheric Modelling using GPS to Calibrate the MWA. I: Comparison of First Order Ionospheric Effects between GPS Models and MWA Observations

GHz radio images from both the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) and the Australia Telescope Large Area Survey (ATLAS) in combination with mid-infrared images at

The LOFAR long baseline snapshot calibrator survey

3.4\,\mu

Spectral Energy Distribution and Radio Halo of NGC 253 at Low Radio Frequencies

m from the {\it Wide-field Infrared Survey Explorer} (WISE) and at