Huub R ö ttgering, Philip Best, Matt Jarvis, John Conway, Matt Lehnert, Marcus Brüggen, Peter Barthel, George Miley, Raffaella Morganti, Ignas Snellen on behalf of the survey team Surveys with LOFAR

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p. 3 Why surveys? LOFAR is a natural survey instrument –Large field of view: 30 MHz : ~10 degrees Low radio frequency imaging is all sky imaging –Cf Hipparcos, Gaia –Need information from a large fraction of the sky for proper calibration of for example the ionosphere A natural compliment to other key programs –Reionisation –Transient surveys Data reduction is a real challenge and computer intense: delivering final data products is a real challenge –A linux cluster of 1000 pc needed for data reduction A well defined set of surveys will maximize the scientific usage of LOFAR (cf. Sloan)

LOFAR performance fully understood? LOFAR performance fully understood? Definition of surveys Optimization For a broad range of topics, including the magnetism Optimization For a broad range of topics, including the magnetism Planning Coordination with transients and EOR Planning Coordination with transients and EOR Execution Key drivers Yes No

Detectability sweet spots (100 km;1 beam 8 MHz) MHz and 150 MHz MHz Integration time [hours] Based on Pandey, Nijboer et al. 2008

Survey speed (100 km; 1 beam 8MHz) Sweet spots: MHz (!) and 120 MHz MHz Area/Unit time [sqr def/hr]

p. 7 LOFAR observes new parameter space Radio frequency interference Correlator capacity/data rates Complicated station beam Ionosphere p. 7

p. 8 GMRT observations at 150 MHz

p. 9 Ionosphere and dynamic range MHz, 80’’ res.,12 deg. FOV Field based calibration ionospheric fitting Intema etal

p. 10 Key Drivers 100 z ~ 6 radio galaxies –Formation and evolution of massive galaxies, black holes and clusters 100 cluster radio sources at z ~ 0.6 –Dynamics of cluster gas, evolution of cluster wide magnetic fields 10 clusters of starbursts starbursts at z>2 –SFR ~ 10 M 0 /yr at z=2-3 Serendipity –<< 30 MHz

p. 11 MRC : a brightest cluster galaxy assembly at z=2.2 ACS/HST imagingMiley et al. ApjL While mass of central stellar component is very high (>10 11 M 0 ), star-forming companions seen in the UV add little additional mass: Elements of both `hierarchical’ and `monolithical’ formation processes

Proto-cluster searches around HzRgs are biased Combine deep Herschel and LOFAR surveys to get a large sample with Δ z_phot = 0.3 p. 12 LOFAR Herschel

p. 13 Simulations of combined LOFAR and Herschel observations of distant galaxies on the basis of semi-analytical galaxy formation models as developed by the Virgo Consortium. The part of the simulations that is shown is a 120 * 20 arcmin projected slice centred on a progenitor of a nearby massive cluster at z=1.8 with a mass of solar masses. Green are the proto-cluster galaxies detectable by LOFAR and Herschel, orange are field galaxies detectable both by Herschel and LOFAR, blue are the LOFAR only detections and the grey dots trace the dark matter particle distribution (with Overzier and Groves)

p. 14 Clusters and LOFAR Low-z (Bruggen, Roediger, Cassano, Orru, Giancintucci ) AGN feedback and studies of cavities on long time scales (>10 8 ) yr Magnetic field strength and configuration, energetics of radio halos Cluster weather through morphologies of extremely old tailed radio sources and starburst galaxies Inventory of shocks traced by radio emission in (merging) clusters and even the cosmic web Intermediate-z Sample of ~ 100 clusters at z~0.6 with diffuse emission ~ 100 at z~0.6 (Ferrari) Cluster lensing studies (Garrett) Location of radio sources wrt to LSS High-z Sample of z>2 proto-clusters through the study of high RM sources in combination with Herschel Very High-z Environment of z>6 radio galaxies

p GHz Clarke and Ensslin, 2006 Relic, Halo, 6 head tails radio galaxies

p. 16 HR et al. 1996

p. 17 WSRT Observations 150 MHz Detection halo + extreme tail: > 1000 Mpc (?) LOFAR: deep maps low frequency maps at 50 times this resolution α~-2 α~-3 continuumSpectral index map

p. 18 Two types of shocks? Large&external Small internal A simulation on the basis of the models of Hoeft and Brüggen (2007) of a LOFAR observation of the diffuse synchrotron emission from magnetised and shocked regions in a massive (10 15 solar mass) galaxy cluster. GMRT+Chandra: Double relic in a triple merger ZW ? Van Weeren, Raychaudhury, Ensslin, Clarke, HR 4 Mpc

p. 19 XMM-LSS survey 10 sqr degree of XMM data Spitzer Swire survey CFHTLS (u,g,r,i,z) survey with 3 million galaxies GMRT and VLA surveys 74, 230, 325 and 610 MHz Complete catalogue with for each object: –Phot-z, galaxy mass, specific sfr, AGN loudness, density of its environment Tasse, HR, Best, Cohen,Le Bourgne, Pierre et al.

p. 20 Summary z~ 0.6 Radio galaxies with Log(M/Mo) > 10.5 –Similar space density as locally –Located in overdensities of scale 450 kpc –Do not have IR excess Identify with accretion of hot gas z~0.6 radio galaxies with Log(M/Mo) < 10.5 –Factor of ~10 higher space density as locally –located in overdensities of scales of 75 kpc –Have an IR excess Identify with merging event driving cold gas to the center LOFAR + IR surveys: trace this up to z=2 p. 20

p. 21 Other important topics AGN and radio source physics –Giant radio sources –Young radio sources –AGN activity as function of redshift, mass, environment etc. Nearby normal galaxies/dwarf galaxies/starburst galaxies –Warm ism –Halo Lensing –Strong lensing by galaxies –Strong lensing by clusters Large scale structure –Radio emission from filaments –Clustering of radio sources –Baryonic oscillations Galactic –Supernova Remnants –HII regions –Exo-planets –Pulsars

p. 22 LOFAR performance fully understood? LOFAR performance fully understood? Definition of surveys Optimization For a broad range of topics, including the magnetism Optimization For a broad range of topics, including the magnetism Planning Coordination with transients and EOR Planning Coordination with transients and EOR Execution Key drivers z>6 radio galaxies z~2.5 protoclusters z~0.6 clusters Serendipity Key drivers z>6 radio galaxies z~2.5 protoclusters z~0.6 clusters Serendipity Yes No

p. 24 Tier FRI and FRII at z>6 Serendipity –15,30, 60 MHz surveys at same effective depth ~100 radio halos at z~0.6 –All sky at 120 MHz Halo LF(z) (Ensslin&HR, 2002) Radio galaxy LF(z) Wilman, Jarvis etal. 2008

p. 25 Tier 1 ~ 100 FRI and FRII at z>6 –15,30, 60 MHz surveys at same effective depth ~100 radio halos at z>0.6 –All sky at 120 MHz 1000 sq.deg at 200 MHz –prohibitively expensive to image the whole sky at 200 MHz. 200 sq. deg. coverage of some of the outer regions of the field observations 60 cluster or supercluster fields, spread in redshift 60 nearby galaxies 60 fields centred on exciting high-z objects, e.g. z ∼ 6 optical quasars. –The depth of these observations is set to match those of the 120 MHz observations for α = − 0.7.

p. 26 Tier2 Major science drivers –cosmic evolution of star forming galaxies, –of radio-loud and radio-quiet AGN activity, –detailed studies of the targetted nearby galaxies and clusters. ~20 fields –13 famous blank-field regions with superb degree-scale multi- wavelength data; –6 nearby clusters or superclusters; –6 nearby galaxies. Depths –30 and 60 MHz deep regions are chosen to match the depth of the 120 MHz all-sky data for α = −1.6. –The 120 MHz deep field data close to the confusion limit –The 200 MHz deep field data matches the depth of the 120 MHz deep field data for α = −0.7

p. 27 Tier3: ultra deep Clusters of Starbursts – with 10 M/yr at z=2 –with 100 M/yr at z=6 5 pointing at 150 MHz

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p. 29 Core Team –Huub R ö ttgering, Philip Best, Matt Jarvis, John Conway, Matt Lehnert, Marcus Brüggen, Peter Barthel, George Miley, Raffaella Morganti, Ignas Snellen Members (45) –Proposed by the partaking countries –Specific expertise, specific access to data/telescopes

p. 30 Next steps Coordination –Transients: proper timing (=small BW) –EOR, Magnetism: wide BW Discussion within the science groups of the overall plans Definition of Commissioning plans Advance ideas on the long baselines Friday afternoon: –Discussion of the plans and organization issues –input from the science groups p. 30

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p. 32 Search for non-AGN Diffuse shocked radio emission p. 32 GMRT 610 MHz Van Weeren Bruggen, Cohen, HR

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