1. Mapping the circumnuclear dust in nearby AGN with MIDI Konrad R.W. Tristram, Klaus Meisenheimer Max-Planck-Institut für Astronomie Heidelberg, Germany Collaborators: Walter Jaffe, David Raban, Bill Cotton

2. 22.08.2006Konrad R. TristramPage 2 Motivation Unified AGN model: Geometrical effects lead to different manifesta- tions (e.g. Seyfert 1 & 2) Our goal: Resolve the dust distri- bution directly for nearby AGN Broad Line Region Accretion Disk Obscuring Torus Ionisation Cone Black Hole

3. 22.08.2006Konrad R. TristramPage 3 Circinus: the galaxy Spiral galaxy SA(s)b, i = ~65° RA = 14h 13m, DEC = −65° 20’ Seyfert type 2 4 × 10 6 M  nucleus Distance ~4 Mpc → 50 mas ~ 1 pc unresolved in MIR 2MASS J, H, K s colour mosaic

4. 22.08.2006Konrad R. TristramPage 4 Circinus: MIDI observations The Circinus UV coverage: 21 fringe tracks, 16 photometries Period 72, 04-02 (U3-U2) Period 73, 04-06 (U3-U2) Period 74, 05-02 (U3-U4) Period 75, 05-05 (U2-U3) Period 77, 06-05 (U2-U3) -80-60-40-2020406080 u in m -80 -60 -40 -20 20 40 60 80 v in m U2-U4

5. 22.08.2006Konrad R. TristramPage 5 Circinus: total flux 8910111213 Wavelength in µm 0 5 10 15 20 Flux in Jy Circinus, total flux from all observations

6. 22.08.2006Konrad R. TristramPage 6 Circinus: correlated flux 8910111213 Wavelength in µm 0.0 0.5 1.0 1.5 2.0 Flux in Jy PA= 44°, BL=49.4m PA= 54°, BL=51.1m PA= 57°, BL=51.7m PA= 88°, BL=58.2m PA=120°, BL=62.0m PA=131°, BL=62.4m Circinus, observed: 2005-02-28 N

7. 22.08.2006Konrad R. TristramPage 7 Circinus: modeling Two blackbody Gaussians: -2000200 -200 0 200 DEC in mas RA in mas11 µm Log of model flux distribution at 11µm Size:σ 1 = 9 mas Ellipticity:ε 1 =0.61 Temperature:T 1 =400 K Filling factor:f 1 =1.0 Size:σ 2 =42 mas Ellipticity:ε 2 =0.03 Temperature:T 2 =300 K Filling factor:f 2 =0.5 Silicate depth:τ SiO =1.3 Position angle:α =60°

8. 22.08.2006Konrad R. TristramPage 8 Circinus: environment Known geometry 1’’~ 20 pc O[III] Expected torus configuration Wilson et al. 2000

9. 22.08.2006Konrad R. TristramPage 9 Circinus: model result RA in mas DEC in mas -75-50-25255075 -75 -50 -25 25 50 75 1.9 pc 0.4 pc Dust torus in Circinus supports unified scheme

10. 22.08.2006Konrad R. TristramPage 10 Centaurus A (NGC 5128) Elliptical galaxy RA = 13h 25m DEC = −43° 01’ Radio jet 6 × 10 7 M  nucleus Distance 3.8 Mpc → 53 mas ~ 1 pc Merger

11. 22.08.2006Konrad R. TristramPage 11 Centaurus A: results 8910111213 0.0 0.5 1.0 1.5 2.0 Flux in Jy PA~108°, BL~60.3m PA~ 37°, BL~45.3m Total Photometry Wavelength in µm N No dusty torus in Centaurus A

12. 22.08.2006Konrad R. TristramPage 12 Conclusions Circinus: –small hot and large cold component –orientation perpendicular to ionisation cone Centaurus A –weak extended dust component –major emitter in MIR: synchrotron source Weaker targets: –hardly resolved Paranal, February 2005