1. Dr Katherine Inskip Montse Villar-Martín (IAA Granada) Clive Tadhunter, Joanna Holt, Dan Dicken (Sheffield) Raffaella Morganti (ASTRON) Friday 20 th October 2006 Extended Emission Line Regions: Nature, origins & implications

2. Friday 20th October 2006The Central Engine of Active Galactic Nuclei2 The data PKS1932-46 VIMOS data: ~210 minutes over 3 nights Includes useful emission lines: H  – [SII]6731 PKS2250-41 VIMOS data: ~200 minutes over 4 nights (and several months…!) Includes useful emission lines: [OII]3727 – [SII]6731 ° (offset from radio axis) Long-slit optical FORS1 spectrum at PA~70 ° (offset from radio axis) Also have Spitzer photometry of both sources, and optical/IR imaging

3. Friday 20th October 2006The Central Engine of Active Galactic Nuclei3 So, what can we learn? Distribution of line-emitting material Ionization state of the gas Density and temperature diagnostics Gas kinematics – relative velocities and line widths Pros: all the usual tools/results of narrow-band imaging and long-slit spectra, plus the ability to tune into regions of interest. Cons: Targeted observations give better depth, and a less restrictive FOV.

4. Friday 20th October 2006The Central Engine of Active Galactic Nuclei4 FRII radio galaxy at z=0.231 RA: 19 h 35 m 56.6 s  : -46°2041.8  (J2000) FRII radio galaxy at z=0.231 RA: 19 h 35 m 56.6 s  : -46°2041.8  (J2000) PKS1932–464 PA -9° spectra (63° offset from radio axis) show 150kpc knotty, star-forming EELR. PA -9° spectra (63° offset from radio axis) show 150kpc knotty, star-forming EELR.

5. Friday 20th October 2006The Central Engine of Active Galactic Nuclei5 IFU fly-through: PKS1932-46

6. Friday 20th October 2006The Central Engine of Active Galactic Nuclei6 IFU fly-through: PKS1932-46

7. Friday 20th October 2006The Central Engine of Active Galactic Nuclei7 Host galaxy at z=0.23; extension to E, +further emission just beyond radio lobe More blobs in surrounding IGM, including star-forming blobs to south Possible companion galaxy to NE PKS1932-46: – fitting the [OIII] emission

8. Friday 20th October 2006The Central Engine of Active Galactic Nuclei8 PKS1932-46: – fitting the [OIII] emission Line widthLine shift Northern blob bright in [OII]3727  shocks?… but from what? Relative velocities vary by ~600kms -1 … but generally line widths suggest quiescent material. O and S line ratios consistent with n e ~100cm -3 and T ~ few 10 4 K.

9. Friday 20th October 2006The Central Engine of Active Galactic Nuclei9 The companion galaxy… z=0.229 (cf. 0.231 for PKS1932-46) [OIII]/H  ~1  star formation! Also, v. bright in Spitzer data. Narrow blueshifted emission around PKS1932-46 host galaxy – same redshift as companion Obvious question: Is this an interacting system? Did interaction trigger AGN activity? Clearly a very messy system! 24  m70  m

10. Friday 20th October 2006The Central Engine of Active Galactic Nuclei10 IFU fly-through: PKS2250-41 [OIII]5007 (left) and [OII]3727 (right) FRII radio galaxy at z=0.308 RA: 22h53m03.1s  : -40°5746  (J2000)

11. Friday 20th October 2006The Central Engine of Active Galactic Nuclei11 IFU fly-through: PKS2250-41 [OIII]5007 (left) and [OII]3727 (right) FRII radio galaxy at z=0.308 RA: 22h53m03.1s  : -40°5746  (J2000)

12. Friday 20th October 2006The Central Engine of Active Galactic Nuclei12 IFU fly-through: PKS2250-41 [OIII]5007 (left) and [OII]3727 (right) FRII radio galaxy at z=0.308 RA: 22h53m03.1s  : -40°5746  (J2000)

13. Friday 20th October 2006The Central Engine of Active Galactic Nuclei13 PKS2250-41: – EELR Ionization State As expected, we can clearly pinpoint shocked region near hotspot. Elsewhere, gas appears photoionized. [OIII]5007Å [OII]/[OIII] [OII]3727Å

14. Friday 20th October 2006The Central Engine of Active Galactic Nuclei14 PKS2250-41: – EELR [OIII] kinematics Most extreme line widths observed near AGN and along jet axis, not near hotspot. Distant regions – narrow line widths. Apparent rotating structure. Similar kinematics observed in FORS1 spectrum Narrow line regions (~150-220kms -1 ) with broad-ish (400-500kms -1 ) blue wings: Observed near hotspots and towards centre of EELR Ionization state suggests shocks/post-shock gas Also see broadening on south side of EELR, seemingly unconnected with radio source kinematics/shock ionization

15. Friday 20th October 2006The Central Engine of Active Galactic Nuclei15 Ionized gas pointing towards the nearby galaxy [OIII] image Cont. image ~ 12’’ or 54 kpc FORS1 spectrum of PKS2250-41: – the very extended emission line region [OIII] image, not continuum subtracted

16. Friday 20th October 2006The Central Engine of Active Galactic Nuclei16 The faint emission in the western lobe: Balmer absorption detected in companion galaxy suggests similar redshifts

17. Friday 20th October 2006The Central Engine of Active Galactic Nuclei17 Concluding thoughts… Radio source/EELR interactions fairly well understood, but… Origin of EELR gas is not! Links with questions of AGN triggering and galaxy growth. Many similarities between PKS2250-41 and PKS1932-46: Radio source strongly interacting with EELR Can we disentangle cause/effect when it comes to clumpy IGM/halo material?

18. Friday 20th October 2006The Central Engine of Active Galactic Nuclei18 Concluding thoughts… similarities cont.: Strong potential for merger/interactions in local environment Both sources have close companions, and emission from blobs lying well off the radio axis Gas kinematics – narrow FWHM at a variety of velocity offsets Other activity: Evidence for star formation in blobs Overall: radio galaxy halos are interesting, unsettled environments, with a lot of physics going on – and it’s not just shocks! Potential to greatly improve our understanding of the triggering process and links to interactions, and ongoing AGN-related feedback

19. Friday 20th October 2006The Central Engine of Active Galactic Nuclei19 VIMOS : VIMOS in IFU mode: Medium resolution grism: useful spectral range of ~4900-9500Å Spatial scale of 0.67  per fibre. FOV of 27x27  in a single pointing.

20. Friday 20th October 2006The Central Engine of Active Galactic Nuclei20 N E PKS1932-46: – fitting the [OIII] emission Host galaxy at z=0.23; extension to E, +further emission just beyond radio lobe More blobs in surrounding IGM, including star-forming blobs to south Possible companion galaxy to NE A fairly convincing M2 star template spectrum!

21. Friday 20th October 2006The Central Engine of Active Galactic Nuclei21 PKS2250-41: – EELR Ionization State 1 23 4 5 6 7 10 8 9

22. Friday 20th October 2006The Central Engine of Active Galactic Nuclei22 PKS2250–41 Recent papers on PKS2250-41: Tilak et al, 2005, AJ, 130, 2513 Villar-Martin et al, 1999, MNRAS, 307, 24 Clark et al, 1997, MNRAS, 286, 558 FRII radio galaxy at z=0.308. RA: 22 h 53 m 03.1 s  : -40°5746  (J2000) RA: 22 h 53 m 03.1 s  : -40°5746  (J2000) Radio lobes aligned roughly east-west, ~18  ~80kpc) in extent. Radio lobes aligned roughly east-west, ~18  ~80kpc) in extent. Extended emission line region (EELR) of similar extent. Extended emission line region (EELR) of similar extent. Extensive arc of line emission in well-studied Western lobe (see Clark et al, 1997, MNRAS, 286, 558). n e ~170cm -3 in arc; T~10 4 K in nuclear region, ~50% higher in arc. Arc contains > 2x10 6 M  gas Clear evidence for interactions between EELR and radio source More irregular emission to the east [For  0 =0.3,   =0.7, H 0 =70kms -1 Mpc -1, the angular scale is 1  ~ 4.5kpc]

23. Friday 20th October 2006The Central Engine of Active Galactic Nuclei23 Collaborators Montse Villar-Martín (IAA Granada) Clive Tadhunter (Sheffield) Joanna Holt (Sheffield) Dan Dicken (Sheffield) Raffaella Morganti (ASTRON)

24. Friday 20th October 2006The Central Engine of Active Galactic Nuclei24 PKS2250–41 Recent papers on PKS2250-41: Tilak et al, 2005, AJ, 130, 2513 Villar-Martin et al, 1999, MNRAS, 307, 24 Clark et al, 1997, MNRAS, 286, 558 FRII radio galaxy at z=0.308. RA: 22 h 53 m 03.1 s  : -40°5746  (J2000) RA: 22 h 53 m 03.1 s  : -40°5746  (J2000) Radio lobes aligned roughly east-west, ~18  ~80kpc) in extent. Radio lobes aligned roughly east-west, ~18  ~80kpc) in extent. Extended emission line region (EELR) of similar extent. Extended emission line region (EELR) of similar extent. Extensive arc of line emission in well-studied Western lobe (see Clark et al, 1997, MNRAS, 286, 558). n e ~170cm -3 in arc; T~10 4 K in nuclear region, ~50% higher in arc. Arc contains > 2x10 6 M  gas Clear evidence for interactions between EELR and radio source More irregular emission to the east [For  0 =0.3,   =0.7, H 0 =70kms -1 Mpc -1, the angular scale is 1  ~ 4.5kpc]

25. Friday 20th October 2006The Central Engine of Active Galactic Nuclei25 PKS2250-41: – results from emission line imaging Eastern region of EELR much fainter/more diffuse Western arc – see lowest ionization state & broad-ish blue wings near extension of radio hotspot; presumably gas compression/shocks. Complex mixture of ionization mechanisms: AGN photoionization, shock ionization with ionizing precursor region, and cooling gas behind.

26. Friday 20th October 2006The Central Engine of Active Galactic Nuclei26 Long-slit FORS1 spectrum, mis-aligned with the radio source axis [OIII] image The Inner 4” region of the EELR

27. Friday 20th October 2006The Central Engine of Active Galactic Nuclei27 Regions with multiple velocities expected. Generally reproduce long- slit results Central regions and quiescent material seem consistent with rotation Narrow line regions (~150-220kms -1 ) with broad-ish (400-500kms -1 ) blue wings: Observed near hotspots and towards centre of EELR Ionization state suggests shocks/post-shock gas Narrow line regions (~150-220kms -1 ) with broad-ish (400-500kms -1 ) blue wings: Also see broadening on south side of EELR, seemingly unconnected with radio source kinematics/shock ionization Complex kinematics: the usual suspects, and a few oddities… 1 23 4 5 6 7 10 8 9

28. Friday 20th October 2006The Central Engine of Active Galactic Nuclei28 FRII radio galaxy at z=0.308 RA: 22 h 53 m 03.1 s  : -40°5746  (J2000) PKS2250–41 Eastern region of EELR much fainter/more diffuse Western arc – see lowest ionization state & broad-ish blue wings near extension of radio hotspot; presumably gas compression/shocks. Complex mixture of ionization mechanisms: AGN photoionization, shock ionization with ionizing precursor region, and cooling gas behind.