Abstract

The Low Frequency Array (LOFAR) Surveys Key Science Project is undertaking an extensive 150MHz radio continuum survey of the entire northern sky that has a diverse array of science goals; encompassing the star-formation and black hole accretion histories of the Universe, the formation and evolution of galaxy clusters, magnetic fields and the interstellar medium. However, achieving these goals requires knowledge of the redshifts and emission mechanisms behind these radio sources. With every observation comprising 16 Terabytes of data and the ionosphere causing distortions on scales of arc-minutes, reaching these scientific goals represents an extreme challenge. However, thanks to recent advances in the radio interferometry and distributed computing techniques, progress in the last year has been remarkable. I will present updates on this fantastic new probe of the Universe, including details of several forthcoming data releases (including ~400sq.deg over the HETDEX spring field) that will open a huge new parameter space for studies of super-massive black hole and cluster formation.

Finally, I will present details of an extensive spectroscopic follow-up campaign using WEAVE, a multi-object spectrograph to be installed on the 4.2m William Herschel Telescope. Commencing in 2019, the WEAVE-LOFAR survey will obtain over a million high-resolution optical spectra for LOFAR selected sources, providing redshifts and source classifications for an unprecedented sample of high redshift AGN. Together these datasets will be truly transformational, providing a complete picture of black hole accretion over the bulk of cosmic history and discovering radio galaxies in the epoch of reionization that will provide unique new probes of this critical process.