Radio Continuum Surveys with Square Kilometre Array Pathfinders
  In the lead-up to the Square Kilometre Array (SKA) project, several
next-generation radio telescopes and upgrades are already being built around
the world. These include APERTIF (The Netherlands), ASKAP (Australia), eMERLIN
(UK), VLA (USA), e-EVN (based in Europe), LOFAR (The Netherlands), Meerkat
(South Africa), and the Murchison Widefield Array (MWA). Each of these new
instruments has different strengths, and coordination of surveys between them
can help maximise the science from each of them. A radio continuum survey is
being planned on each of them with the primary science objective of
understanding the formation and evolution of galaxies over cosmic time, and the
cosmological parameters and large-scale structures which drive it. In pursuit
of this objective, the different teams are developing a variety of new
techniques, and refining existing ones. Here we describe these projects, their
science goals, and the technical challenges which are being addressed to
maximise the science return.
