Download presentation
Presentation is loading. Please wait.
Published byDuane Smith Modified over 9 years ago
1
Atacama Large Millimeter/submillimeter Array Expanded Very Large Array Robert C. Byrd Green Bank Telescope Very Long Baseline Array Radio source surveys and populations Ken Kellermann National Radio Astronomy Observatory
2
Radio Survey Discoveries Radio galaxies (1949) Cosmic evolution (1955) Quasars (1963) IPS (1964) Pulsars (1967) Gravitational lenses (1979) June 13, 2013Georgefest2
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, 2013Georgefest3
4
Radio Source Surveys 1000 hr 2400 hr 2000 hr 1700 hr 13,000 hr Georgefest4 Norris et al., 2013 3000 hr
5
“Positions of Three Discrete Sources of Galactic Radio-Frequency Radiation” – Bolton, Stanley, and Slee, 1949 Radio galaxies 1954 Cygnus A, z = 0.05 Baade & Minkowski, 1954 M87 NGC 5128 Crab June 13, 2013Georgefest5
6
Radio Source Counts Sydney Mills Cross Bernie Mills Cambridge 2C and 3C Martin Ryle Georgefest6 X = - 3 X = -1.85
7
Radio Source Surveys VLA, WSRT, ATCA, GMRT Molonglo 100 MHz – 22 GHz e-MERLIN, LOFAR, ASKAP, MeerKAT, SKA All Sky surveys Cosmology-Large Scale Structure FR I & FR II Radio Galaxies, RL Quasars NVSS FIRST WENSS SUMSS AT20 Limited Area Surveys Populations – Galaxy Evolution AGN, SFG, RQ Quasars E-CDFS HDFN HDFS COSMOS SWIRES - Lockman Hole Phoenix Georgefest7
8
Condon (1984) compilation FR I & FR II Radio Galaxies – Quasars Kellermann et al., 2008 Owen & Morrison, 2008 8 June 13, 2013
9
JVLA Observations of the Owen- Morrison field (SWIRE) Lockman Hole) Georgefest9
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 Georgefest10 Problems μJy count discrepancy natural confusion at 100 nJy Non thermal sky temperature O&M 2008 Condon 2012 Condon 1989 Log Jy
11
ARCADE 2 – Excess Sky Brightness Georgefest11 3, 8, 10, 30, 90 GHz (Fixen et al. 2011)
12
Sky background implications survey limits ARCADE 2 Condon, 1989; Wilman 2008 Condon et al., 2012
13
VLA Survey of the CDFS June 13, 2013Georgefest13
14
Georgefest14 Chandra Deep Field South 4 Msec exposure 740 X-ray sources S >10 -17 ergs/sec GOODS-S HST 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 UDF 976 ks exposure B, V, I, z 10,000 galaxies mag 29 ESO 2.2m/WFI z < 27.3 Spectra - VLT 7.5 μJy VLA 6.5 μJy
15
Star forming galaxies Radio-FIR: q ~ 1.7 R = log(S r /S V ) < 1.7 L r < 10 24 W/Hz Not E galaxy L x < 10 42 ergs/sec No VLBI component Padovani et al. in preparation RL AGN R > 1.4 L x > 10 42 ergs/sec L x > 10 42 ergs/sec NIR (IRAC) colors NIR (IRAC) colors FIR: q < 1.7 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 Georgefest 15 June 13, 2013
16
Quasi-stellar Galaxies June 13, 2013Georgefest16
17
Radio Loud and Radio Quiet QSOs Two 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 Georgefest17
18
JVLA Observations of SDSS QSOs Georgefest18 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, 2013Georgefest19
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.