Low Frequency Science with the Square Kilometre Array

Abstract

Over the past several years an international community of scientists and engineers has emerged with a common goal to solve the technical challenge required to construct a giant radio telescope with a collecting area of one square kilometre. The Square Kilometre Array (SKA) will have a hundred times more collecting area than our most powerful existing radio telescopes, providing sensitivity of a few tens of nanoJy in the centimetre/decimetre wavelength continuum. With a spatial resolution better than the Hubble Space Telescope, a field of view larger than the full moon, and the ability to simultaneously image a wide range of red shift, the SKA will be the worlds premier spectroscopic imaging telescope at any waveband.At long wavelengths the SKA will be able to detect emission from atomic hydrogen gas at extreme redshifts, allowing study of the “Dark Ages” of the Universe, before, and during, the transition phase when the initial stars formed and reionization occurred. The combination of sensitivity, wide field of view and high angular resolution, will allow high resolution imaging of the interstellar media and magnetic field of a vast number of galaxies to high redshift. Measurements of atomic hydrogen emission and continuum emission will trace the star formation history of the Universe from primordial galaxies to the present.