1. Extra-planar Gas – Dwingeloo, June 2004 Raffaella Morganti (Astron) Extra-planar Gas – Dwingeloo, June 2004 Outflows of neutral hydrogen in AGN T. Oosterloo, C. Tadhunter, B. Emonts, J. Holt 1500 km/s

2. Extra-planar Gas – Dwingeloo, June 2004 Detection of neutral hydrogen in the central regions of active galaxies: commonly associated with circumnuclear tori/disks. but this is not always the case (perhaps not even the majority). Disturbed/complex kinematics of the gas is observed and provides a more complete picture of what is happening in these regions i.e. presence and occurrence of gas outflows. NGC 4261 Planar and extra-planar HI in AGNs

3. Extra-planar Gas – Dwingeloo, June 2004 Issues related to AGN Outflows They can affect the evolution of the host galaxy and its ISM They influence the ionization of the medium What structure they have, or how much mass and energy they carry. They can tell us about the ISM and the interplay between this medium and the radio source Outflows in high z radio galaxies

4. Extra-planar Gas – Dwingeloo, June 2004 Importance of gas and outflows in high-z radio galaxies Large Ly  halos At low-z these effects are less extreme but… Pentericci et al. van Ojik et al. 1997 strong blue-ward asymmetries in the Ly  emission lines: due to cold gas associated with the radio galaxy the HI absorption can be extended and stronger in smaller radio galaxies

5. Extra-planar Gas – Dwingeloo, June 2004 Issues related to AGN Outflows They can affect the evolution of the host galaxy and its ISM They influence the ionization of the medium What structure they have, or how much mass and energy they carry. Outflows in high z radio galaxies: Outflows in Seyferts: optical and UV

6. Extra-planar Gas – Dwingeloo, June 2004 Blue-shifted absorption lines in many species of several hundred to over 1000 km/s. Kriss et al. 1995 Gas outflows in Seyfert galaxies Hutchings et al. 1998

7. Extra-planar Gas – Dwingeloo, June 2004 Issues related to AGN Outflows They can affect the evolution of the host galaxy and its ISM They influence the ionization of the medium What structure they have, or how much mass and energy they carry. Outflows in high z radio galaxies: Outflows in Seyferts: optical and UV Starburst winds AGN (radiation) driven outflow Jet driven outflows Possible origin of outflows in AGNs

8. Extra-planar Gas – Dwingeloo, June 2004 How about nearby radio galaxies?  Evidence of outflows in ionized gas  Clear cases of radio galaxies embedded in very rich ISM (far-IR bright, CO etc.)  They possibly represent the radio galaxies originating from major mergers: young stellar population observed Study in HI of these cases

9. Extra-planar Gas – Dwingeloo, June 2004 WSRT Deep absorption: Haschick & Baan (1985) Beswick et al. (2002) broad, shallow absorption by neutral gas Morganti et al. ApJL (2003) Broad absorption  ~0.15% N H ~2 x 10 20 cm -2 for T SPIN =100K Broad HI absorption in 3C293

10. Extra-planar Gas – Dwingeloo, June 2004 Broad HI absorption in 4C12.50 Broad absorption  ~ 0.2% N H ~10 20 cm -2 for T SPIN =100K WSRT observations, 20 MHz band Broad HI absorption: full width of ~2000 km/s mostly blueshifted ADD FIGURA????? HST image in [OIII] (Axon et al.) VLBI (Stanghellini et al.) 100pc

11. Extra-planar Gas – Dwingeloo, June 2004 Schilizzi et al. 2001 O’Dea et al. 2001 Optical depth of the broad absorption  ~0.15% ~1500 km/s Broad HI absorption in 3C236

12. Extra-planar Gas – Dwingeloo, June 2004 Other cases: 3C459 800 km/s Optical depth of the broad absorption  ~0.05% Thomasson et al. 2003 ~2 kpc

13. Extra-planar Gas – Dwingeloo, June 2004 ~ ~ 1000 km/s Jackson et al. 2002 ~3 kpc WSRT observations MERLIN+HST Broad HI absorption in 3C305 Optical depth of the broad absorption  ~0.08%

14. Extra-planar Gas – Dwingeloo, June 2004  Relatively high number of objects with broad HI absorption in radio galaxies with young stellar population: biased result? Very low optical depth  need very strong radio continuum mostly  In these objects the broad HI is mostly blueshifted (compared to the systemic velocity)  outflows What we find so far: - Location of the absorption - Relation with the ionized gas Next

15. Extra-planar Gas – Dwingeloo, June 2004 HI OII Emonts et al. in prep Core Blueshifted wing at location of lobe red: radio continuum (MERLIN, Beswick et al.) blue: CO (Evans et al.) 1’’ Ionized and neutral gas in 3C293 it would correspond to a mass of the HI ~3x10 6 M sun

16. Extra-planar Gas – Dwingeloo, June 2004 [OIII]4959,5007 fit with 3 components Ionized and neutral gas in 4C12.50 Holt et al. 2003 Stratified outflow: broader (and highly reddened) component of ionized gas coming from the inner regions  blueshifted component(s) also in the ionized gas  broader width compared to HI Young source surrounded by (and interacting with ) a cocoon of material left over from the even that trigger the radio source.

17. Extra-planar Gas – Dwingeloo, June 2004 Other cases: 3C459 800 km/s Optical depth of the broad absorption  ~0.05% Thomasson et al. 2003 ~2 kpc No HI absorption in high resolution (VLBI) data

18. Extra-planar Gas – Dwingeloo, June 2004 3C459: HI and ionised gas [OIII]  width of the ionized gas much larger in this case, is the deeper HI component to be blueshifted

19. Extra-planar Gas – Dwingeloo, June 2004  Relatively high number of objects with broad HI absorption in radio galaxies with young stellar population: biased result? mostly  In these objects the broad HI is mostly blueshifted (compared to the systemic velocity)  outflows  Indication that at least in some cases the HI absorption (and the broad optical lines) happens off-nucleus (~ 1 kpc)  case of IC 5063 What we find so far:

20. Extra-planar Gas – Dwingeloo, June 2004 The case of the radio-loud Seyfert IC 5063 H  +[NII] ~4arcsec circa 1.3kpc ATCA & NTT radio core Vel ATCA – 17 GHz

21. Extra-planar Gas – Dwingeloo, June 2004  Similarities with the ionized gas (a blueshifted component is always seen in neutral and ionized): are the two outflows due to the same mechanism?  The width of the optical lines could be systematically larger: could indicate that they come from different regions? What we find so far:  Relatively high number of objects with broad HI absorption in radio galaxies with young stellar population: biased result? mostly  In these objects the broad HI is mostly blueshifted (compared to the systemic velocity)  outflows  Indication that at least in some cases the HI absorption (and the broad optical lines) happens off-nucleus (~ 1 kpc)  case of IC 5063

22. Extra-planar Gas – Dwingeloo, June 2004  Starburst wind  Post-starburst galaxies (typical ages between 0.5 and 2 Gyr )  Adiabatically expanded broad emission line clouds (Elvis 2002)  located in the nuclear regions  Radiation pressure+Dust (Dopita et al.) Despite the very energetic phenomena involved, gas remains - or becomes again - neutral Insight on the physical conditions of the medium around the AGN What produces the HI outflows  Interaction between the radio jet and ISM

23. Extra-planar Gas – Dwingeloo, June 2004 Interaction between the radio jet and ISM: a possible scenario

24. Extra-planar Gas – Dwingeloo, June 2004 Mellema et al. 2002 looks promising also to explain the broad HI BUT can the fragmented clouds be accelerated to such high velocities? Evolution of clouds in radio galaxy cocoons: shock runs over a cloud compression phase (overpressured cocoon) fragmentation & cooling formation of dense, cool & fragmented structures What jet/cloud interaction can do for us? Simulations show that cooled fragmented clouds do form as result of the interaction Mellema et al. 2002, Fragile et al. 2003

25. Extra-planar Gas – Dwingeloo, June 2004 How common is broad HI absorption?  Relatively large number of objects with broad HI absorption in radio galaxies with young stellar population: suggesting a rich medium around these radio sources (against which the radio plasma is interacting)? biased result? probably yes!  Not in every radio galaxy (few cases without)  But some new cases …………

26. Extra-planar Gas – Dwingeloo, June 2004 Some new cases…… Taylor et al. (2004) 4C37.11 Optical depth of the peak absorption  ~0.3% ~ 1500 km/s WSRT Very little known about the optical ………… VLBA

27. Extra-planar Gas – Dwingeloo, June 2004 A recent new case: OQ208  known to have fast outflow in the broad emission lines (Marziani et al.)  particularly rich medium from X-ray absorption: radio jets possibly piercing their way through a Compton-thick medium pervading the nuclear environment (Guainazzi et al. 2004) ~10 pc Stanghellini et al. 1993 Optical depth of the peak absorption  ~0.5% WSRT 1500 km/s

28. Extra-planar Gas – Dwingeloo, June 2004 Relevant for the evolution of the radio sources the radio jet has to “fight” against a rich medium: the jet is not confined but can be momentarily disrupted (slowing down the evolution of the radio source) If the interaction between the radio emission and the ISM is so important

29. Extra-planar Gas – Dwingeloo, June 2004 Rich ISM against which the jet has to fight against in order to expand out of the galaxy “Fighting” its way out 4C12.50 Core Mass of the HI cloud ~10 5-6 M sun High column density (N H ~10 22 cm -2 ) HI absorption VLBI Morganti et al. 2004 A&A in press 2D simulations Bicknell et al. 2003 radio jet dense cloud black=WSRT red = VLBI Integrated HI profile

30. Extra-planar Gas – Dwingeloo, June 2004 Conclusions  Fast outflows (~ 1000 km/s) and disturbed kinematics of the neutral hydrogen in the central regions of radio galaxies  Fast HI outflows possibly coming from jet interacting with the ISM  Relatively large number of objects with broad HI absorption in radio galaxies with young stellar population: suggesting a rich medium around these radio sources?  Relevant for the evolution of the radio sources: the radio jet has to “fight” against a rich medium. The jet is not confined but can be momentarily disrupted.

31. Extra-planar Gas – Dwingeloo, June 2004 Conway & Schilizzi 2000 Narrow absorption from VLBI WSRT beam

32. Extra-planar Gas – Dwingeloo, June 2004 V sys VLBI ~300 pc PKS 1814-63

33. Extra-planar Gas – Dwingeloo, June 2004 Correspondence with ionized gas PKS 1814-63 ATCA data [OIII] 4959,5007Å ESO-NTT

34. Extra-planar Gas – Dwingeloo, June 2004 How all this compares with other Seyfert galaxies? Considered mainly affected by the interaction between the radio and the ISM but more recently: nuclear wind important (e.g. dust+radiation pressure model of Dopita et al.) DESCRIVERE FIGURA!!!! DESCRIVERE RESULTS FOR N1068

35. Extra-planar Gas – Dwingeloo, June 2004 The case of the Seyfert galaxy IC 5063 radio core H  +[NII] ~4arcsec circa 1.3kpc ATCA & NTT radio core 400 km/s

36. Extra-planar Gas – Dwingeloo, June 2004 Considered to be very important for high-z radio galaxies, Nearby examples: Minkowsky object: van Breugel et al. (1985) Even closer example: Centaurus A NGC 541 15 kpc (see talk by van Breugel) Possible connection with jet induced star formation

37. Extra-planar Gas – Dwingeloo, June 2004 How common is broad HI absorption?  Relatively high number of objects with broad HI absorption in radio galaxies with young stellar population: suggesting a rich medium around these radio sources? biased result? probably yes! Sample of compact sources Vermeulen et al. 2003  Not in every radio galaxy (few cases without)