Download - Radio source surveys and populations
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