The radio continuum view of The radio continuum view of Centaurus ACentaurus A

Ron Ekers CSIRO The Many Faces of Centaurus A Sydney, 29 June 2009

Ilana’s composite

Morganti et al. 1999

9°

10’ Burns et al. xx

image courtesy Norbert Junkes (MPIfR) Why Centaurus A is specialWhy Centaurus A is special

■ the first extragalactic radio source ■ the brightest source in the Southern Hemisphere ■ the second double lobed source discovered – after Cygnus A ■ the closest Radio Galaxy ■ the closest AGN ■ the closest SMBH – VLBI resolution 0.01pc, 100 Rs ■ A spectacular galaxy

Evolution of the Models Evolution of the Models

■ Radio sources – Static magnetic field 1960 – Evolutionary sequence 1970 – Continuous injection – Continuous reacceleration ■ Energy source – Galaxy collisions 1950’s – Nuclear accretions 1960­ – Accretion triggered by collisions 1980­

Centaurus ACentaurus A the closest AGN the closest AGN

■ Distance 3.4Mpc ■ Next closest comparable AGN M87 17Mpc ! ■ Average distance to a L=1024 W Hz­1 radio galaxies – 10Mpc – So we are lucky (or influenced!) ■ Much easier to study at all wavelengths ■ Subtends a large angular size – Good linear resolution – Background probes

Some Radio GalaxiesSome Radio Galaxies

Name Size Log Log (kpc) Luminosity Energy (ergs sec­1) (ergs) Centaurus A 470 41.7 59.9

Cygnus A 200 45.2 60.6

M87 80 42.0 58.6

M82 1 39.5 55.2

Polarization in Centaurus APolarization in Centaurus A

Bracewell 1962 ■ April 1962 ■ Parkes 64m just completed ■ Discovered by Bracewell – Published Cooper and Price – Visitors Log – Not a National Facilities yet! ■ Connie Mayer – Found Cygnus A polarization a few weeks earlier

North Goobang Philosophical Society North Goobang Philosophical Society Mark Price 1961Mark Price 1961

Discovery of Faraday RotationDiscovery of Faraday Rotation Centaurus A ­ Parkes 64m Centaurus A ­ Parkes 64m

■ Cooper and Price ■ Nature Sep 1962 ■ 10 – 20cm ■ Faraday Rotation o – ­120

Cooper Price and ColeCooper Price and Cole 19651965

■ Aust J Phys, 18, 589 (1965) ■ Parkes 64m ■ 11, 21, 31, 75cm ■ Spectral index ­0.6 whole source ■ Polarization up to 40% ■ RM ­36 to ­84 rad m­2

Haslam 408MHzHaslam 408MHz

Haslam 408MHz HIPASS ContinuumHIPASS Continuum

Preliminary continuum image, courtesy Mark Calabretta (CSIRO ATNF) HI Parkes All Sky SurveyHI Parkes All Sky Survey Barnes et al. 2001Barnes et al. 2001

■ Observations 1997 to 2000 ■ 8° scans of 9 minutes ■ Mark Calabretta (ATNF) processing continuum ■ incl. HI Zone of Avoidance Juraszek et al 2000

Preliminary continuum image, courtesy Mark Calabretta (CSIRO ATNF) Feain 2009 Parkes 6cmParkes 6cm Norbert Junkes Norbert Junkes

Intensity Polarization

600kpc

???

Centaurus ACentaurus A ATCA MosaicATCA Mosaic

■1.4GHz continuum ■ full polarization ■4 x 750m array configuration 600kpc ■406 pointings, hexagonal grid ■Σ FOV 45 deg2 ■Θ ~45’’ ■ σ ~0.26mJy/beam (0.1K)

■Ilana Feain – last talk! Centaurus A compositeCentaurus A composite

Radio – Optical alignmentRadio – Optical alignment Radio Radio – Optical alignmentRadio – Optical alignment Precession?Precession?

Optical

150kpc 60kpc

Cannon, UK Schmidt IIIaJ [How] does radio plasma couple [How] does radio plasma couple to the IGM/ISM?to the IGM/ISM? CO blue stars

Charmandaris+00 Graham & Fassett 02

30kpc

Oosterloo+05 Star FormationStar Formation Centaurus A middle lobeCentaurus A middle lobe

Oosterloo

Galex UV

15kpc

Thermal Xray in the Middle Thermal Xray in the Middle LobeLobe

Oosterloo

15kpc

Kraft et al ApJ 698 (2009) 2036

Centaurus A compositeCentaurus A composite

Inner double lobeInner double lobe VLA 5GHzVLA 5GHz

7 kpc

Inner double lobeInner double lobe

7 kpc

Centaurus A compositeCentaurus A composite

Centaurus A Centaurus A the closest AGN jetthe closest AGN jet

■ ATCA 5GHz – Hardcastle 2003 ■ Chandra Xray 1 kpc – Kraft 2002 – 1” = 17pc

Centaurus A the Centaurus A the Asymmetry Asymmetry EnigmaEnigma 3pc

Many scales of Centaurus AMany scales of Centaurus A 600kpc – 0.01pc = 10600kpc – 0.01pc = 108 : 1 : 1

■ Mpc overall shape ­ modified by dynamical changes? ■ 100Kpc middle lobe ­ bubbles, star­formation, channels – jet induced star formation – We cant understand the physics of black hole regulation and feedback except in the very closest objects. ■ 10kpc ­ central double ■ 1kpc jet – closest so best resolution – Xray ­ radio ■ 0.01pc VLBI jet – One sidedness – Doppler, flip­flop, environment – SMBH effects, accretion disk, BH merger kicks

Parkes Parkes Norbert Junkes Norbert Junkes

600kpc

image courtesy Norbert Junkes (MPIfR)Feain 2009 Junkes to FeainJunkes to Feain

150kpc