We present the data and initial results from the first pilot survey of the Evolutionary Map of the Universe (EMU), observed at 944 MHz with the Australian Square Kilometre Array Pathfinder (ASKAP) telescope. The survey covers $270 \,\mathrm{deg}^2$ of an area covered by the Dark Energy Survey, reaching a depth of 25–30 $\mu\mathrm{Jy\ beam}^{-1}$ rms at a spatial resolution of $\sim$ 11–18 arcsec, resulting in a catalogue of $\sim$ 220 000 sources, of which $\sim$ 180 000 are single-component sources. Here we present the catalogue of single-component sources, together with (where available) optical and infrared cross-identifications, classifications, and redshifts. This survey explores a new region of parameter space compared to previous surveys. Specifically, the EMU Pilot Survey has a high density of sources, and also a high sensitivity to low surface brightness emission. These properties result in the detection of types of sources that were rarely seen in or absent from previous surveys. We present some of these new results here.

Detection of the late time integrated Sachs-Wolfe effect (ISW) is an active area of study related to Large Scale Structures (LSS).The ISW effect can be studied by observing the nonzero cross-correlation between cosmic microwave background (CMB) anisotropies with tracers of mass field, such as galaxy survey data. We plan to study this effect by crosscorrelating the CMB data and related cosmological parameters as delineated by the Wilkinson microwave anisotropy probe (WMAP) with the upcoming evolutionary map of the universe (EMU) survey planned for Australian square kilometer array Pathfinder(ASKAP). EMU-ASKAP is planned to conduct a deep radio continuum survey with rms 10µJy/beam. The survey is planned to cover the entire southern sky, extending to North + 30 degree declination. To infer the expected redshift distribution (dN/dz) and differential source count (S) of the survey that can be extracted from the EMU galaxies, we use data from Scubed simulation of extra-galactic radio continuum (S 3 -SEX) for square kilometer array design studies (SKADS). We also calculate various parameters including galaxy survey shot noise, rms confusion uncertainty, and position uncertainty for the survey which can help in understanding the accuracy and analyzing the results of the data. We also discuss Signal to noise ratios over range of maximum redshifts and maximum multipole values with some discussion on constraints over ΩΛ and Ωb.

We present a novel natural language processing (NLP) approach to deriving plain English descriptors for science cases otherwise restricted by obfuscating technical terminology. We address the limitations of common radio galaxy morphology classifications by applying this approach. We experimentally derive a set of semantic tags for the Radio Galaxy Zoo EMU (Evolutionary Map of the Universe) project and the wider astronomical community. We collect 8,486 plain English annotations of radio galaxy morphology, from which we derive a taxonomy of tags. The tags are plain English. The result is an extensible framework which is more flexible, more easily communicated, and more sensitive to rare feature combinations which are indescribable using the current framework of radio astronomy classifications.

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