LOFAR surveysProbing the formation and evolution of massive galaxies, AGN, and clusters

Huub RöttgeringLeiden Observatory

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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)

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LOFAR performance fully understood?

Definition of surveys Optimization

For a broad range of topics, including the magnetism

PlanningCoordination with

transients and EOR

Execution

Key drivers

Yes

No

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Survey speed (100 km; 1 beam 8MHz) Sweet spots: 15-60 MHz (!) and 120 MHz

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• 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

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Key Drivers1. 100 z ~ 6 radio galaxies 2. 100 cluster radio sources at z ~ 0.6 3. 10 clusters of starbursts starbursts at z>24. 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

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• 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, – α30

60=-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

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• 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

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• Clusters of starbursting galaxies with 20-30 M/yr at z=2.5: 100M/yr at z=8)

• Targetting famous extra-galactic fields

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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

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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,

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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

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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

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