Extragalactic surveys with LOFAR

Organisers: Huub Röttgering, Peter Barthel,

George Miley, Raffaella Morganti, Ignas Snellen.

LOFAR, the Low Frequency Array, is a next-generation radio telescope that is being built in the Netherlands and expected to be fully operational at the end of this decade.  It will operate at frequencies from 15 to 240 MHz (corresponding to wavelengths of 20 to 1.2 m). Its superb sensitivity, high angular resolution, large field of view and flexible spectroscopic capabilities will represent a dramatic improvement over previous facilities at these wavelengths. As such, LOFAR will carry out a broad range of fundamental astrophysical studies and will be an important vehicle for astronomical research in the Netherlands.

An important goal that has driven the development of LOFAR since its inception is to explore the low-frequency radio sky by means of a series of unique surveys. We are planning to exploit the unprecedented sensitivity and wide instantaneous field of LOFAR to conduct large-sky surveys at 15, 30, 60, 120 and 200 MHz.  Such surveys should start in 2009, when the 100 km LOFAR should become operational.

Four topics are driving the definition of the proposed surveys. These are:

Formation of massive galaxies, clusters and black holes using z> 6 radio galaxies as probes, Intercluster magnetic fields using diffuse radio emission in galaxy clusters as probes, Star formation processes in the early Universe using starburst galaxies as probes, and Exploration of new parameter space for serendipitous discovery.

A survey science team consisting of about 20 members has been setup. Its task it is to:

provide input for planning the surveys and subsequent production, plan preparatory/follow-up observations, carry out  theoretical simulations, be involved in / take the lead in one of the science areas.

We are planning to have a first meeting of this team at the Lorentz Center March 6-8, 2007.

Presentations will take about 60 % of the time leaving ample time for discussions too. These discussions will focus on:

Does the current set of survey cater for our needs? What scientific topics do need more input? How do we get organised? Can we plan/prioritize the various surveys/fields/frequencies? What needs to be done as preparatory and follow-up observations?