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arXiv · 1810.06672

Probing $\Lambda$CDM cosmology with the Evolutionary Map of the Universe survey

José Luis Bernal·Alvise Raccanelli·Ely D. Kovetz·David Parkinson·Ray P. Norris·George Danforth·Courtney Schmitt
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Abstract

The Evolutionary Map of the Universe (EMU) is an all-sky survey in radio-continuum which uses the Australian SKA Pathfinder (ASKAP). Using galaxy angular power spectrum and the integrated Sachs-Wolfe effect, we study the potential of EMU to constrain models beyond $\Lambda$CDM (i.e., local primordial non-Gaussianity, dynamical dark energy, spatial curvature and deviations from general relativity), for different design sensitivities. We also include a multi-tracer analysis, distinguishing between star-forming galaxies and galaxies with an active galactic nucleus, to further improve EMU's potential. We find that EMU could measure the dark energy equation of state parameters around 35\% more precisely than existing constraints, and that the constraints on $f_{\rm NL}$ and modified gravity parameters will improve up to a factor $\sim2$ with respect to Planck and redshift space distortions measurements. With this work we demonstrate the promising potential of EMU to contribute to our understanding of the Universe.

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José Luis Bernal, Alvise Raccanelli, Ely D. Kovetz, David Parkinson, Ray P. Norris, George Danforth, Courtney Schmitt. 2018-10-15. Probing $\Lambda$CDM cosmology with the Evolutionary Map of the Universe survey. https://doi.org/10.1088/1475-7516%2F2019%2F02%2F030

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