Australia Telescope 20 GHz survey (AT20G): An Update Ron Ekers (ATNF, PI),Sarah Burke(Haverford-Swinburne), Mark Calabretta (ATNF), Gianfranco De Zotti (Padua), Paul Hancock (U Sydney), Carole Jackson (ATNF), Michael Kesteven (ATNF), Marcella Massardi (SISSA-ATNF), Tara Murphy (U Sydney), Katherine Newton-McGee (U Sydney), Chris Phillips (ATNF), Roberto Ricci (ATNF), Elaine Sadler (U Sydney), Lister Staveley-Smith (ATNF), Mark Walker (MAW Tech), Jasper Wall (UBC), Warwick Wilson (ATNF) - VSOP-2 09 Mar 2007

CMB MissionsCMB Missions Calibrator manuals for radiotelescopesCalibrator manuals for radiotelescopes ALMA ATCA SKA Radio Source population studiesRadio Source population studies WMAP & PLANCK Motivations

CMB foreground removal Extragalactic radio source contamination

Number of pointings  2 Flux S  -0.7 Time per pointing  S -2 Survey time  cm survey takes 240 x 6cm survey Surveying problem

GHzRicci et al AT20G 22.8 GHz 15 (33) GHz 15 GHz Freq. 4015,288 38% sky 4406 AT20G 1000All sky323Hinshaw et al (WMAP3) Waldram et al (9C) Taylor et al.2001 S lim (mJy)Area (sq. deg.)Source no.Project Existing Surveys at high frequency

WBCORR Wide Band analogue correlator Frequency range GHz Bandwidth 8GHz (8 frequency channels) All sky in 10(15)degree declination regions includes galactic plane No delay correction possible scan along the meridian High scan rate High scan rate: 15 deg./min

Sky Coverage Missing Data

Combine the scans to make maps Candidate Sources

The Survey Blind scan Calibration Map making Selection criteria LIST OF CANDIDATES Follow 20GHz Observation of the candidates LIST OF SOURCES LIST OF SOURCES Follow 4.8 and 8.6 GHz low frequency observations of the confirmed sources DATA ON EACH SOURCE PIPELINE of data analysis flagging calibration data reduction polarization analyses imaging AT20G CATALOGUE

AT20G follow-up 20 GHz FU: Oct 2004, H214 array, GHz, BW 128 MHz - region -30/-50 deg => 1400 sources confirmed at 5 sigma Spectra FU: Nov 2004, 1.5 array, 4.8/8.6 GHz, BW 128 MHz 20 GHz FU: Oct 2005, H168 array, GHz, BW 128 MHz - region -50/-90 deg => 1300 sources confirmed at 5 sigma Spectra FU: Nov 2005, 1.5 array, 4.8/8.6 GHz, BW 128 MHz 20 GHz FU: 29 Apr-03 May 2006, H214 array, GHz, 128 MHz -region -50/-90 deg => 1200 sources confirmed at 5 sigma Spectra FU: June 2006, 1.5 array, 4.8/8.6 GHz, 128 GHz 20 GHz FU: Oct 2006, H214 array, GHz, 128 MHz -region -30/-15 deg => 1400 sources confirmed at 15 sigma Spectra FU: Nov 2006, 1.5B array, 4.8/8.6 GHz, 128 MHz

Equal area sky maps of the AT20G follow-up sources ( ) 4406 extragalactic sources detected in sq. deg. Polar projectionAitoff projection

AT20G source counts Integral source counts Normalized differential counts

Spectral index from AT20G extragalactic sources 280 extragalactic sources All AT20G sample Bright Sample (S 20 > 0.5 Jy) 11% 53% 13% 22% 8%20% 29%43% Massardi et al in prep.

AT20G Polarization Properties 5GHz8GHz18GHz Mean2.43%2.63%2.83% Median2.19%2.18%2.10% Max8.02%9.38%10.66% S 20 >500mJy;  < -30º ~200 sources observed 5GHz8GHz18GHz Burke et al in preparation

Gravitational lens search Spectral index ( GHz) Amp(6)/Amp(no6) PKS Plot courtesy of R.Chhetri

Clean-up follow-ups (C1049: -90°<dec< -15º)Clean-up follow-ups (C1049: -90°<dec< -15º) Follow-up of galactic objects (UCHII: Murphy et al in prep.)Follow-up of galactic objects (UCHII: Murphy et al in prep.) 3mm follow-up (C1392: Sadler et al in prep.)3mm follow-up (C1392: Sadler et al in prep.) Variability studies ( : Sadler et al. 2006)Variability studies ( : Sadler et al. 2006) Polarization studies (C1633: Burke et al in prep.)Polarization studies (C1633: Burke et al in prep.) Upcoming data release (BSS: Massardi et al in prep.)Upcoming data release (BSS: Massardi et al in prep.) Search for grav. lenses (CLASS in the South: Chhetri et al.) Search for grav. lenses (CLASS in the South: Chhetri et al.) The Future of AT20G