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LOFAR surveys Probing the formation and evolution of massive galaxies, AGN, and clusters Huub Röttgering Leiden Observatory. Today. Recent changes in the survey plan Beam sizes and survey speeds Frequency setups Overall changes to the plan Commissioning plans Not today Science case
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LOFAR surveysProbing the formation and evolution of massive galaxies, AGN, and clustersHuub RöttgeringLeiden Observatory
Today • Recent changes in the survey plan • Beam sizes and survey speeds • Frequency setups • Overall changes to the plan • Commissioning plans • Not today • Science case • Ionospheric calibration • Implemented calibration method: Spam (Intema et al.) • Ionospheric description form the VLSS (Cohen et al.) • Analytic model of ionospheric fluctuations (vd Tol et al)
Key drivers Definition of surveys Optimization For a broad range of topics, including the magnetism Planning Coordination with transients and EOR No LOFAR performance fully understood? Yes Execution
Survey speed (100 km; 1 beam 8MHz) Sweet spots: 15-60 MHz (!) and 120 MHz
General: wide band to improve UV coverage, calibration, optimize data for MKSP • 15 MHz: performance uncertain • 30/60 MHz: simultaneously observations would compromise sensitivity or survey speed. • 120 MHz: workhorse survey • 150 MHz: go as deep as possible • 200 MHz: high resolution • with input from Heald, Anderson, Beck
Key Drivers • 100 z ~ 6 radio galaxies • 100 cluster radio sources at z ~ 0.6 • 10 clusters of starbursts starbursts at z>2 • Serendipity • << 30 MHz • Plus a long list of important topics • Clusters, AGN studies, Lensing, Galaxies, the Galaxy • Cautionary notes: • Variation of sky brightness • Tapering of the station beam to reduce side lobe levels • Low elevation operations • RFI • Ionospheric calibration
120 MHz: workhorse survey: • depth and are driven by ~100 radio halos at z~0.6 • 15,30, 60 MHz: • driven by ~ 100 hzrgs at z~6, • α3060=-1.6, α1530=-1.3 • 200 MHz • 250 pointings/1500 deg2: matching 60 MHz with α=-0.75 200 sqr degrees famous fields, 60 clusters, 60 nearby galaxies, 60 exciting objects • Shallow all sky
120 MHz: starburst galaxies (z=0.5: 10 M/yr; z=2.5: 100Mhz); • 25 regions: 50% famous blank fields, rest clusters, and other interesting regions • Status nearby galaxies? • 30 and 60 MHz matches all sky with α = -1.4 • 200 MHz matches 120 MHz with α = -0.8
Clusters of starbursting galaxies with 20-30 M/yr at z=2.5: 100M/yr at z=8) • Targetting famous extra-galactic fields
First list of Commissioning plans • A few ``Deep’’ fields at full range of frequencies • Low and high elevation • 7 pointings in a hexagonal grid • Coma A at a range of frequencies • A giant radio source • Deep observations at a very bright source • Galactic center
Iteration scheme • Feb-March: draft • March 24: telecon • April 7: update with detailed input also from MKSP • End of April: telecon with SW chairs • May 18+19: technical meeting at ASTRON, elaborate commissioning plans • June17-19 • `Finalise’ (commissioning) plans, discuss MS3,
Core team • Executive body • Members • appointed by national consortia • Selected for specific expertise • Current composition • Huub Rottgering, Philip Best, Peter Barthel, Philip Best, Marcus Brüggen, Gianfranco Brunetti, Krzysztof Chyzy, John Conway, Matt Jarvis, Matt Lehnert, George Miley, Raffaella Morganti, Ignas Snellen
Science group (SG) and chairs • The highest redshift radio sources - George Miley • Starforming galaxies at moderate and high redshifts- Matt Lehnert • Clusters and cluster halo sources - Marcus Brüggen/Torsten Ensslin • AGN at moderate redshifts - Philip Best • Gravitational lensing - Neal Jackson • Detailed studies of low-redshift AGN - Raffaella Morganti • Nearby galaxies - John Conway • Cosmological studies - Matt Jarvis • Galactic radio sources – Marijke Haverkorn / Glenn White