Atacama Large Millimeter/submillimeter ArrayExpanded Very Large Array

Robert C. Byrd Green Bank TelescopeVery Long Baseline Array

Radio source surveys and populations

Ken KellermannNational Radio Astronomy

Observatory

Georgefest 2

Radio Survey Discoveries

• Radio galaxies (1949)• Cosmic evolution (1955)• Quasars (1963) • IPS (1964)• Pulsars (1967) • Gravitational lenses (1979)

June 13, 2013

Georgefest 3

Radio source surveys and populations

• Radio source surveys– History– Curent status– Problems

• VLA and JVLA Deep Surveys– CDFS & ECDFS– Lockman Hole (SWIRES)

• Populations– Strong source population – MicroJy population– NanoJy population?

• RQ Quasars

June 13, 2013

Georgefest 4

Radio Source Surveys

1000 hr

2400 hr

2000 hr

1700 hr

13,000 hr

Norris et al., 2013

3000 hr

Georgefest 5

“Positions of Three Discrete Sources of Galactic Radio-Frequency Radiation” –

Bolton, Stanley, and Slee, 1949

Radio galaxies

1954 Cygnus A, z = 0.05Baade & Minkowski, 1954

M87 NGC 5128Crab

June 13, 2013

Georgefest 6

Radio Source Counts

SydneyMills Cross

Bernie Mills

Cambridge2C and 3C Martin Ryle

X = - 3

X = -1.85

Georgefest 7

Radio Source Surveys VLA, WSRT, ATCA, GMRT Molonglo

100 MHz – 22 GHze-MERLIN, LOFAR, ASKAP, MeerKAT, SKA

All Sky surveysCosmology-Large Scale Structure

FR I & FR II Radio Galaxies, RL Quasars

• NVSS• FIRST• WENSS• SUMSS• AT20

Limited Area SurveysPopulations – Galaxy Evolution

AGN, SFG, RQ Quasars

• E-CDFS• HDFN• HDFS• COSMOS• SWIRES - Lockman Hole• Phoenix

Georgefest

Condon (1984) compilationFR I & FR II Radio Galaxies – Quasars

Kellermann et al., 2008

Owen & Morrison, 2008

8June 13, 2013

Georgefest 9

JVLA Observations of the Owen- Morrison field (SWIRE) Lockman Hole)

• α = 10h46m00s, δ = +59°01 00″′• (2 GHz BW)• C configuration (3-km)• θ = 8 arcsec• τ = 50 hrs• σn = 1.0 μJy• σc = 1.2 μJy

Georgefest 10

• Sample Variance – NO• Noise bias• Statistical weight corrections• primary beam• Bandwidth smearing• Time smearing corrections• Multiple component sources• Resolution

corrections

MicroJy Radio Source Counts

Problems• μJy count discrepancy• natural confusion at 100 nJy• Non thermal sky temperature

O&M 2008

Condon 2012

Condon 1989

Log Jy

Georgefest 11

ARCADE 2 – Excess Sky Brightness

3, 8, 10, 30, 90 GHz (Fixen et al. 2011)

𝑇 𝑏 (3𝐺𝐻𝑧 )=54±6𝑚𝐾

Sky background implicationssurvey limits ARCADE 2

𝑁>6 𝑥104𝑎𝑟𝑐𝑚𝑖𝑛2

Condon, 1989; Wilman 2008

Condon et al., 2012

Georgefest 13

VLA Survey of the CDFS• Chandra 4 Msec Survey (Xue et al. 2011)

– 740 X-ray sources– ergs/sec

• VLA Survey (Miller et al., ApJS 205, 2013) – 20 cm; 240 hrs; 6 pointings; Ω = 0.3 deg – VLA C configuration (1.6 x 2.8 arcmin resolution)– σ = 6.4 μJy– 883 radio sources S > 37 μJy

• 268 detected at X-rays (Vattakunnel et al, 2010)

• 839 (95%) OIR counterparts – 678 (82%) redshifts - 274 spectroscopic (Bonzini et al. 2012)– Spitzer IRAC SIMPLE 3.6, 4.5, 5.8, 8 μm (91%) (Damen et al. 2010)– Spitzer MIPS FIDEL 24 μm (88%) (Dickenson et al. 2007)

• Population Classification (Bonzini et al. submitted)June 13, 2013

Georgefest 14

Chandra DeepField South

4 Msec exposure740 X-ray sourcesS >10-17 ergs/sec

GOODS-SHST B, V, I, z < 28

IRAC 3.6, 4.5, 5.8. 8.0 μm MIPS FIDEL 24 μm

MUSYC K (VLT) < 22.4

Hubble UDF976 ks exposure

B, V, I, z10,000 galaxies

mag 29

ESO 2.2m/WFI z < 27.3Spectra - VLT

7.5 μJyVLA

6.5 μJy

Star forming galaxiesRadio-FIR: q ~ 1.7

R = log(Sr/SV) < 1.7 Lr< 1024 W/HzNot E galaxy

Lx < 1042 ergs/secNo VLBI component

Padovani et al. in preparation

RL AGN • R > 1.4• Lx > 1042 ergs/sec• NIR (IRAC) colors• FIR: q < 1.7

RQ AGN• R 1.4• Lx > 1042 ergs/sec• NIR (IRAC) colors• FIR: q ~ 1.7

μJy radio sources• SFG• AGN

• RL AGN • RQ AGN (SF)

S > S > 1 mJy

• FR I & FR II RG• RL Qusars

Georgefest15June 13, 2013

Georgefest 16

Quasi-stellar Galaxies

June 13, 2013

Georgefest 17

Radio Loud and Radio Quiet QSOsTwo populations?

Separate Population• Kellermann et al., 1989, 1994• Miller, et al, 1990, 1993• Sopp & Alexander, 1991• Visnovsky et al., 1992• Peterson, 1997• Kukula et al., 1998• Krolik, 1999• Kembhavi & Narlikar, 1999• Ivezic, et al., 2002, 2004• Laor, 2004• Jiang et al. 2007• White et al., 2007• Zamfir et al., 2008• Balokovic et al., 2012• Kimball et al., 2011• Condon et al., 2013

Continuous Distribution

• White et al. 2000• Lacy et al., , 2001• Cirasuolo, et al. 2003• Barvainis, et al., 2005• Rafter et al., 2009• Mahony et al. 2012

18

JVLA Observations of SDSS QSOs

• 179 SDSS QSOs

• ; Mi < - 23

• RQ QSOs W/Hz• RQ QSOs due to SF in host

galaxy

Georgefest

Kimball et al. 2012, ApJ ,739, L29

19

Summary• All Sky surveys sample powerful radio galaxies and quasars

– S > 1 mJy– First indication of cosmic evolution.

• microJy radio sources are driven by a mixture of SF and SMBHs

• RQ QSOs differ from RL QSOs and are powered primarily by star formation in the host galaxy.

• ARCADE 2 observations suggest a population of nanoJy sources not associated with galaxies

• Number Counts rapidly converge at low flux desnities– SKA will not be limited by natural confusion

• The JVLA is by far the most sensitive radio telescope available– Will learn more about submicroJy population June 13, 2013 Georgefest