1. Jet-Gas Interactions in Seyfert Galaxies Mark Whittle (Virginia) David Rosario (Virginia) John Silverman (Virginia) Charlie Nelson (Drake) Andrew Wilson (Maryland)

2. Outline Brief review of : AGN & Jets & Emission lines Reasons to study jet-gas interactions (JGI) Case study of Seyfert Galaxy : Mkn 78 Observations & data overview Heuristic description of JGI Ionization analysis Dynamical analysis

3. Active Galaxies All galaxies have nuclear black holes Those currently accreting are “active” Accretion energy released in two forms

4. A : Photons Thermal & non-thermal processes Broad SED : Optical / UV / X-ray Large range in luminosity : LINER  Seyfert  QSO

5. AGN Spectral Energy Distribution (SED) Radio far-IR optical EUV X-ray

6. Seyferts (NGC 4151) Low Luminosity Quasars High Luminosity

7. B : Bipolar Outflows (Jets) Origin uncertain (MHD driven ?) Velocity uncertain : –Some relativistic, others not Content uncertain : (p + e - or e + e - ?) –Relativistic component : e - + B  radio –Other (thermal) components ? Large luminosity range : –Radio loud (radio galaxies/QSRs) –Radio quiet (Seyferts/QSOs)

9. Radio Galaxy 3C 296 Flux ~ few Jy Radio Loud Seyfert Galaxy Mkn 573 Flux ~ few mJy Radio Quiet

10. From ionized gas : T e ~ 10 4 K, n e ~ 10 2 – 10 9 cm -3 Ionization mechanism ? – Photoionization (yes) – Shock related (maybe with jets?) Profiles reveal (Doppler) velocities BLR (R ~ 10 -2 pc, V 2 ~ GM BH /R) NLR-1 (R ~ 1 kpc, V 2 ~ GM bul /R) NLR-2 (R ~ 1 kpc, V ~ jet related) Nested emission line regions BH << AD << BLR << NLR << Gal r/c : min hr week 10 3 yr 10 4 yr Emission Lines

11. Jet-gas interactions occur in many contexts –AGN (ISM/IGM) –Stellar jets (DMC/ISM) –Starburst winds (ISM/IGM) Laboratory for astrophysical hydrodynamics Seyfert ELRs allow important diagnostics –Gas mass, velocity, KE, momentum, pressure –Complements radio source pressure/energy Why study JGI in Seyferts ?

12. Mkn 78 : jet-gas archetype Early ground based data suggest prominent JGI : Luminous triple radio source Strong double [OIII] profile FWHM >> gravitational velocities

13. Mkn 78

14. Unfortunately, Mkn 78 is quite distant : cz ~ 11,000 km/s  1 arcsec ~ 700pc B T ~ 15.2 M B ~ -20.8 Dull looking early type galaxy  Need HST resolution

15. KPNO 2.1 m Red Continuum 30 arcsec Mkn 78

16. Mkn 78 : HST & VLA Dataset VLA : 3.6cm 8hr map HST images : (FOC, PC, STIS, NICMOS) –Continuum : UV/green/near-IR –Emission line : [OIII] 5007 HST spectra : (STIS, FOS) –4 slits : good spatial coverage –4 gratings : low resolution : UV & optical high resolution : [OIII] 5007

17. Dust lane Optical Near IR arcsec NICMOS F160W STIS CCD clear

18. 3.6cm radio [OIII] λ5007 arcsec

19. [OIII] 5007 Image : ENLR

20. 4 STIS Slit Positions

21. STIS low dispersion spectral data

22. STIS high dispersion [OIII] 5007 data

23. Mkn 78 Case Study : Jet-gas interactions 1.Heuristic description 2.Ionization study 3.Dynamical study 4.Jet properties

24. Overlay : Radio (contours) & [OIII] (image)

25. STIS high dispersion [OIII] 5007 data

26. 1. Heuristic Description 1.Inner W-knot Jet ends & disrupts; some gas disturbance ?  DMC enters & disrupts flow; recent interaction 2.Eastern fan Jet deflected; split lines; “blow-back” shape ?  Cloud inertia deflects jet (doesn’t destroy it) ?  Radial + lateral motion induced (±300 on 400) ?  Intermediate age : begun to disrupt cloud 3.Outer W-lobe Components; complex velocity ; no bow shock ?  late stage; dispersing cloud remnants; leaky bubble

27. 2. Ionization Study Low dispersion spectra  many line fluxes Compare line ratios with : 1.Ionization models (U, A m/i, Shock) 2.Velocities ( V bulk & FWHM ) 3.Location (radius) 4. Other things (radio/color/dust)

28. Ionization mechanisms Three basic contexts explored : 1.U – sequence : AGN photoionization 2.A m/i – sequence : AGN photoionization 3.Shock – sequence : shock ionization Cartoon illustrates these 

29. AGN UV Photo-ionized precursor Collisionally ionized & photo-ionized post-shock gas shock Neutral Back Ionized front Optically Thin clouds V sh 1) U sequence 2) A m/i sequence 3) Shock sequence U = N i /N e ~ 10 -2 – 10 -3 Optically Thick Clouds Only Optically Thick & Thin Clouds A m/i = A m /A i ~ 0.1 – 10 V sh = 100 – 800 km/s Auto-ionizing Shocks Doptia & Sutherland : ‘95, ‘96, ‘03 Binette et al : ‘96 Ferland’s, CLOUDY AGN UV

30. Line ratios vs models Line ratios vs models a)General excitation/ionization b)Discriminators to separate Sh & U+A m/i c)Discriminators to separate U & A m/i d)[ [OI] 6300 anomalous line ] e)[ Nuclear nitrogen enhancement ]

31. U A m/i Sh Excitation : All models OK U ~ 10 -2 – 10 -3 A ~ 30% – 90% Sh ~ 500 – 300 km/s

32. U A m/i Sh Discriminators 1 Trends follow U & A Don’t follow shocks

33. U A m/i Sh Discriminators 2 e.g. [NeV], HeII, & [OIII]4363 U poor, favours A m/i trend fits nicely Note : weak [NeV] in Mkn 78 requires new A m/i

34. 1.Clean results because enough data to show trends 2.Current shock models are excluded 3.Photoionization by the AGN dominates 4.Gas contains both optically thick & thin clouds Ratios vs models : Summary Now consider ratios vs gas velocity 

35. Shock Excitation vs FWHMExcitation vs V –V sys Shock Results summary 

36. 1.Essentially no (v. weak) correlations :  ionization conditions independent of velocity 2.Shock model predictions very poor Ratios vs velocity : Summary Now consider ratios vs radius 

37. Radius : Strong correlation  photoionization U drops ~ r –1  density ~ r –1 [SII] difficult to confirm A m/i drops with r  more thin @ small r Excitation vs Radius

38. Final check : UV Luminosity Check photoionization : –Can UV luminosity power emission lines ? But UV is invisible/obscured ?! Take FIR luminosity = reprocessed UV –L UV ~ L FIR ~ 4 π d 2 F FIR ~ 4 π d 2 [2.6S 60 + S 100 ]  Check : –L UV ~ L em ~ 10 x L 5007 as observed –U ~ N UV /n e ~ 10 -2.5 as observed

39. 3. Dynamical Study To go beyond heuristic description : –Need physical properties –Aim to evaluate these throughout regions –First consider ionized gas –Then consider other components

40. Slit B : kinematic measurements -2 -1 0 +1 +2 +3 East Nuc West Peak Velocity FWHM

41. Mass KE Extinction Density Line flux Momentum

42. Simple Properties Three regions : Inner knot / East fan / West lobe Region Age : Age ~ size/velocity : ~ 0.4 / 4 / 8 Myr Ionized gas : Mass : ~ 0.4 / 1.0 / 1.1 x 10 6 M sun Filling factor : ~ 30 / 1.5 / 0.5 x 10 -4 Covering factor : ~ 0.5 / 0.5 / 0.5 Consider other components 

43. The Various Components ISM n ism ~ 1 Relativistic gas : ff rel ; P rel ~ B 2 /8π Thermal gas : n th ; P th ; T th Line Emitting gas : ff em ; n em ; P em ; V em Assume/show : P rel ~ P th ~ P em ~ P ism

44. Log P / k ~ 6.5 / 6.0 / 5.5 K cm -3 –Quite high > radio galaxy lobes –All components deep within galaxy ISM All pressures drop with radius (~ r -1 ) –As expected for galaxy ISM context Approximate pressure balance between different components : P rel ~ P em (~ P th ) Relativistic & radiation pressure too low to accelerate ionized gas (by ~ x 10) –Need dynamical (ram) pressure of jet Pressures : P rel, P em, P th, P rad

45. Energy Comparisons Relative energies in different parts : –UV (FIR) ~ 1000 (~10 43 erg/s) –Emission lines ~ 1000 –Kinetic ~ 1 –Relativistic ~ 1 –Expansion /lobe ~ 1 –Radio ~ 0.2 Simple inferences 

46. 1.Photons dominate by x 1000 ; L em ~ L UV  supports photo- over shock ionization  should not derive L jet from L em (see later) 2. Expansion / KE / Relativistic all similar  flows can accelerate gas & power radio source Conclusions from energy comparisons

47. 4. Jet Properties Estimating jet energy and momentum : Use emission line & lobe properties : E j ~ KE em + α e E lobe ~ 2-5 E lobe α e = synchrotron loss; adiabatic loss; ff rel L j = E j /T age ~ 2-5 x 10 40 erg/s G j ~ α m G em ~ 2-5 G em α m = covering factor loss ; drag loss F j = G j /T age ~ 2-5 x 10 33 dyne

48. F j ~ α m G em / t age FjFj G em ~ ΣM V JET MOMENTUM JET LUMINOSITY L j ~ (E KE + α e E rel )/t age E lobe ~ PV ~ α e E rel LjLj E KE ~ Σ½M V 2 α e ~ α syn α ad α ff ~ 2 – 10 α m ~ α drag α lcf ~ 2 – 5

49. Jet Properties (model) Components : –Relativistic & thermal; ratio defined by ff rel –Both move at V j Pressure balance : P rel ~ P th –We know P rel from radio physics ~ B me /8 π Energy : E j ~ KE th + W th + W rel –W rel = (4/3)P rel ; W th = (5/2) P th Momentum : G j ~ G th + G rel = G th –Relativistic component has ~zero inertia 2

50. Jet Properties (derived) Use L j G j P j A j to derive many properties (>100pc) Thermal material dominates jet energy and momentum –Relativistic gas has little/no momentum –KE j /U j ~ F j /A j /P j ~ 10 / 3 / 2  KE dominates energy Jet velocity ~ 1-few x V gas –2L j /F j ~ V j ~ 300 – 3000 km s -1 Ram pressure dominates : P ram ~ 30 / 7 / 4 x P rel –Can accelerate to V em over T age for N col ~ 10 21 cm -2 –Only mild shocks : P ram ~ ρ em V sh 2  V sh ~ 10-50 km s -1 –Not acceleration by impulsive shocks; maybe wind/ablation

51. Jet Properties (derived) Jet density (thermal) : 0.1 - 5 cm -3 –Consistent with entrained ISM Jet temperature : T j ~ P j /n j k ~ 10 6 K – ~ 0.1-0.7 Temperature from thermalized V j –again consistent with entrained ISM Jet Mach number : 5 / 2.5 / 2  transonic –Consistent with entrainment and decollimation Jet mass flux : ~ M em over region lifetime –Could be entrained ISM –Could become ‘thermal’ component of lobe

52. Comparison with previous work Many partial interpretations One thorough analysis :  Bicknell, Dopita & Sutherland ’98 They use shocks to infer jet properties, in particular : jet energy & momentum This yields significantly different results

53. L j ~ L em ~ 100 x L 5007 Bicknell et al ‘98 Emission Lines : L em LjLj For Mkn 78 & other Seyferts : L j (them) ~ 1000 x L j (us) JET LUMINOSITY Shock L j ~ (E KE + αE rel )/t age Our analysis E lobe ~ PV ~ αE rel LjLj E KE ~ Σ½M V 2

54. ρ j V j 2 ~ ρ em V sh Bicknell et al ‘98 P ram ~ ρ j V j 2 For Mkn 78 & other Seyferts : F j (them) ~ 100 x F j (us) JET MOMENTUM Shock ρ em V sh 2 V sh ~V em ~ 500 km/s n em ~ 10 3 cm -3 2 Impulsive acceleration Emission Line Cloud F j ~ αG em / t age Our analysis FjFj G em ~ ΣM V Gradual acceleration

55. Comparison : Ours is a kinder, gentler jet. Maybe more plausible ? Jet Property Our Jet Bicknell et al Energy flux Energy flux : L j x 1 x 1000 Momentum flux F j x 1 x 100 Velocity : V j 300 – 3000 km/s (1 – few V em ) 15 – 90 x 10 3 km/s (0.05c – 0.3c) Density : n j 0.1 – 5 cm -3 Ram pressure : P j x 1 x 100 Cloud shock : V sh 10 – 50 km/s 500 – 1000 km/s Temperature : T j ~ 10 6 K ~ 10 9 K Mach No. : M j 2 – 51 – few

56. Summary 1.Jet-gas interactions (JGI) are important 2.VLA & HST data on Seyfert with dominant JGI 3.Inspection reveals likely JGI scenario –3 regions suggest temporal development 4.Ionization study rejects role of shocks –AGN photoionization of thick & thin components 5.Data provide information on jet properties : – relatively low power, low speed, transonic, dense jet – dominated by thermal gas, at T j ~ 0.5 x T(V j ) – ram pressure ~ 2-10 x internal pressure 6.Overall context : thermal jet/wind driven ablata

57. New HST Project : 1 or 2 slits on six other objects with evidence for JGI.