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Matteo Guainazzi European Space Astronomy Center of ESA Villafranca del Castillo (Spain) ‏

Matteo Guainazzi European Space Astronomy Center of ESA Villafranca del Castillo (Spain) ‏. “Did I say radio quiet?” Radio-loudness in radio-quiet Seyferts [and a note on X-ray core spectra in low-power radio RGs]. AGN SED. (Elvis et al. 1994) ‏. Gallery of radio emission in Seyferts.

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Matteo Guainazzi European Space Astronomy Center of ESA Villafranca del Castillo (Spain) ‏

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  1. Matteo Guainazzi European Space Astronomy Center of ESA Villafranca del Castillo (Spain)‏ “Did I say radio quiet?”Radio-loudness in radio-quiet Seyferts [and a note on X-ray core spectra in low-power radio RGs]

  2. AGN SED (Elvis et al. 1994)‏

  3. Gallery of radio emission in Seyferts NGC4395 0.1 pc (VLBI, Wrobel & Ho 2006)‏ (VLBA, Anderson et al. 2004)‏ Unresolved Sub-pc scale Mkn231 (VLA, Gallimore et al. 2006)‏ (VLBA, Ulvestad et al. 1999)‏ pc-scale, sub-relativistic kpc-scale (44% of 43 CfA galaxies – AGN driven)‏

  4. Outline Radio emission in Seyfert galaxies: core and jet emission Jet-ISM interaction and the ionization mechanism of the [E]NLR Lessons and questions on Radio Galaxies core X-ray spectra from Seyfert Galaxies X-ray spectra

  5. Outline Radio emission in Seyfert galaxies: core and jet emission Jet-ISM interaction and the ionization mechanism of the [E]NLR Lessons and questions on RG core X-ray spectra from Seyfert Galaxies X-ray spectra

  6. Multiple scales in individual objects 1.5 kpc 7.5 kpc 1 kpc (Ulvestad et al. 1999)‏ (Kharb et al. 2004)‏ From pc- to kpc-scale in Mkn 231 Internal shock in a jet? (Gallimore et al. 2004)‏ Free-free absorbed, variable Ionized cocoon? Resolved ∟ radio axis Free-free thermal emission from the inner side of the maser disk Multiple kpc-components in Mkn 6 • Combination of: • compact flat-spectrum • extended steep-spectrum NGC1068

  7. Radio-quiet/-loud dichotomoy (Ho & Peng 2001)‏ Seyferts nuclei are not radio-quiet! [60% have R>10, for: R≡Lν(6 cm)/ Lν(B)] Is the radio-loudness (R) distribution bi-modal? YES: Strittmatter et al. (1980), Kellermann et al. (1989), Wadadekar & Kembhhavi (1999), Ivezic et al. (2002), Panessa et al. (2007)‏ NO: White et al. (2000), Hewett et al. (2001), Cirasuolo et al. (2003)‏ • Possible alternative R definitions: • Relative Lradio/LFIR(Rush et al. 1996, Thean et al. 2000)‏ • IRAS severely contaminated by the host galaxy • Relative Lradio/LX(Terashima & Wilson 2003)‏ • Good for highly obscured and LLAGN • Absolute radio power (Miller et al. 1990)‏ • Radio-loudness should be w.r.t. other λλ

  8. Spectral indices (Ulvestad & Ho et al. 2001)‏ (Thean et al. 2001)‏ • Palomar Seyferts have a large • fraction of flat spectra (α≥-0.7)‏ • No optically-thin synchrotron emission • Synchrotron self-absorption? • Free-free emission? • Free-free absorption? • Radiative inefficient accretion? • Link with Giga-Hertz Peaked Sources? • Spectral turnover • Sub-relativistic jets

  9. Radio-power dependence (Doi et al. 2005)‏ 3 Low-luminosity AGN: α = -0.3-0.1 (Ulvestad & Ho et al. 2001)‏ • Pure ADAF models over-predicts the X-ray emission by ≥10 (Yi & Boughn 1998, Quataert et al. 2001)‏ • → Co-presence of an ADAF and a compact jet • Weaker sources have weaker jets → ADAF emission starts become visible at low radio L

  10. Radio-loudness vs. accretion rate (Greene & Ho 2006)‏ (Panessa et al. 2007)‏ • State transition at Lbol/LEdd≈0.01: • Below this value: radiatively inefficient accretion flow + outflow • Above this value: optically-thick, geometrically-thin disk, radiation pressure dominated slim disk

  11. Is there a X-ray/radio correlation? YES: Panessa et al. (2007)‏ NO (distance effect in flux-limited samples): Bianchi et al. (2008)‏

  12. Fundamental plane of BH activity • Scale-invariant jets [Heinz & Sunyaev 2003] • Radio luminosity scales with BH mass and accretion rate, independently of the jet model • Scaling depends on α, and the electron distribution index → on accretion physics only • X-ray emission from BH accretion at a few percent Eddington is consistent with radiative inefficient flow only • In low accretion rate sources, jet power is proportional to accretion power • Challenges? Seyferts and LL RGs seem to follow different planes[Wang et al. 2006; Panessa et al. 2007] (Merloni et al. 2003, 2006; Falcke et al. 2004)‏

  13. Jet/ISM interactions [Earlier results: Wilson & Ulvestad 1982, Oosterloo et al. 2000)] NGC3079 IIIZw2 (Middelberg et al. 2008)‏ (Brunthhaler et al. 2005)‏ 43 GHz (jet hotspots)‏ “Slower-when-brighter” behaviour (Saxton et al. 2005)‏ Interaction with clumpy ISM could “frustrate” the jet in Seyfert galaxies Alternative: continuous emission of “aborted jets” (Ghisellini et al. 2004)‏ 15 GHz (external shell)‏

  14. Outline Radio emission in Seyfert galaxies: core and jet emission Jet-ISM interaction and the ionization mechanism of the [E]NLR Lessons and questions on RG core X-ray spectra from Seyfert Galaxies X-ray spectra

  15. Radio/NLR interaction Correlation between radio and optical power (de Bruyn & Wilson 1978, Wilson & Willis 1980, Heckman et al. 1981, Meurs & Wilson 1984, Whittle 1985, Wilson 1991, Whittle 1992)‏ (Ho & Peng 2001)‏ Jet vs. NLR power Correlation between radio and line width (Wilson & Willis 1980, Whittle 1985, 1992)‏ (Nagar et al. 2005)‏ In LLAGN the jet is the primary output channel of accretion energy (Ulvestad & Ho 2001)‏

  16. Do radio jets affect NLR … Morphology? Contours: radio Grayscale: O[III] (Capetti et al. 1996)‏ (Capetti et al. 1998)‏ Contours: radio Grayscale: O[III] Ionization? position of radio knot (Axon et al. 1998)‏ Kinematics? (Yes, but see Das et al. 2006 for a counter-example on NGC1068)‏

  17. Role of shock ionization (ESO428-G14; Riffel et al. 2006)‏ (NGC2110; Evans et al. 2006)‏ Chandra [Fe II] [O III] 2cm Contribution to ionization by shocks <80-90% <70-80%

  18. Shock ionization (Wilson & Raymond 1999)‏ (Dopita 1995; Dopita & Sutherland 1995)‏ • Ionizing shock model: • Could explain extended soft X-ray emission in obscured AGN (Wilson & Raymond 1999)‏ • Would require a jet dominated by thermal plasma [Bicknell 2002] where radio emission is just a tracer of the underlying flow • “ACIS measurements will be crucial to test it”

  19. Soft X-ray extended emission and NLR Images: O[III] – Contours: soft X-rays 500 pc 600 pc 600 pc 600 pc Circinus Galaxy (Smith & Wilson 2001)‏ NGC4151 (Yang et al. 2001)‏ NGC5643 (Bianchi et al. 2006)‏ NGC1386 (Bianchi et al. 2006)‏ 500 pc 1000 pc 700 pc 2000 pc NGC1068 (Young et al. 2001)‏ NGC5347 (Bianchi et al. 2006)‏ Mkn3 (Sako et al. 2000)‏ NGC3393 (Bianchi et al. 2006)‏

  20. Seyfert soft X-ray spectra NGC1068/RGS (Sambruna et al. 2001)‏ (Guainazzi & Bianchi 2007)‏ Narrow (<10 eV) Radiative Recombination Continua in a sample of Seyfert 2 galaxies with the RGS (Kinkhabwala et al. 2002; Gallimore et al. 2004)‏ (Sako et al. 2000)‏ High-resolution soft X-ray spectra are dominated by AGN photoionization Contribution by thermal plasma negligible (Brinkman et al. 2002, Bianchi et al. 2006)‏

  21. Outline Radio emission in Seyfert galaxies: core and jet emission Jet-ISM interaction and the ionization mechanism of the [E]NLR Lessons and questions on RG core X-ray spectra from Seyfert Galaxies X-ray spectra

  22. X-ray core emission of low-L RGs FRI [Donato et al. 2004; Evans et al. 2006] Unobscured, Г=1.88±0.02 Correlation between X-ray, radio, optical → origin at the base of the relativistically beamed radio jet FRII [Evans et al. 2006] Obscured (NH>1023 cm-2), Г=1.76±0.02, Fe Kα line Torus-surrounded accretion disk emission Soft excess → jet-related origin BLRG [Grandi et al. 2004, 2006, 2007]: Unobscured, disk-dominated emission (beamed contamination ≤70%)‏ Weak Fe Kα line, weak Compton-reflection Anticorrelation between Fe Kα EW and R in heterogeneous radio-loud samples [Reeves & Turner 2000, Grandi et al. 2007]

  23. Seyfert X-ray emission Torus + disk Disk outflow Disk corona Seyfert 2s Disk (how?)‏ Seyfert 1-1.5s Torus + disk (Courtesy of I.George)‏ Unobscured Seyfert 2s (1021 cm-2)‏ (Malizia et al. 1997)‏ There is nothing like a “power-law” X-ray spectrum in Seyfert Galaxies

  24. Open questions If we see the accretion disk in the X-ray spectra of RGs Where are the relativistically smeared features? Is there any Compton reflection? BeppoSAX: weak (Grandi et al. 2006)‏ Where is the warm absorber? Are warm absorber outflows and radio jets two different manifestations of the same underlying medium? Why there is no soft excess in FRI? Which is the true nature of the soft excess in FRIIs? Is the distribution of absorbing column densities consistent between RGs and Seyferts? RG Seyfert (Evans et al. 2006)‏ (Tüller et al. 2008)‏

  25. Soft excess in FRIIs: 3C344 Maximum jet contribution in the soft X-ray band 26 Starburst (after Wu et al. 2002)‏ 3C445 Sy2s pn (Sambruna et al. 2007; Grandi et al. 2007)‏ (Guainazzi 2008)‏ • Soft X-ray emission lines in both the XMM-Newton EPIC and RGS shows that the soft X-ray emission is dominated by AGN-photoionized gas • This constraints the contribution of any jet-related non-thermal emission • These measurements are challenging, but possible. Similar example: 3C33 (Torresi et al., in prep.)‏

  26. Specific Chandra contributions Spatial resolution required to resolve the nuclear emission Spatially resolved low-resolution spectroscopy (coupled with high-throughput, serendipitous high-resolution spectroscopy with the XMM-Newton RGS) is key to understand the nature of the emission on 0.1-1 kpc scale → ionization mechanism of the [E]NLR My pledge for the future: Completeness! (see, e.g., Massaro’s talk)‏

  27. Conclusions At least 50% of Seyfert galaxies are radio emitters on different scales (from sub-pc to kpc-scale)‏ Core radio emission probably due to a combonation of jet and low-efficiency accretion (the latter more important for weak sources)‏ Interaction with (clumpy?) ISM frustrates sub-relativistic jets in radio-quiet AGN Fundamental plane indicative of scale-invariant jet physics Combination of high-resolution measurements in the spatial (Chandra) and spectral (Chandra, XMM-Newton) domain key to rule out shocks as the main source of [E]NLR ionization How close/different are the X-ray cores of Seyfert and Radio Galaxies? We need extended study of complete samples to tell

  28. Back-up material

  29. Statistics (just a few examples!)‏ Paper Sample # Instnt (reson)‏ Detection fraction Morphologies Ho & Ulvestad (1999)‏ Palomar Seyfert 52 VLA (1”)‏ 85% (3σ, 6 cm)‏ 71% (3σ, 20 cm)‏ Unresolved: 52% Slightly resolved: 30% [Linear: 32%] Thean et al. (2001a)‏ CfA 19 MERLIN (0”.1-0”.3)‏ 100% (18 cm; only >2mJy 8.4GHz sources observed)‏ Unresolved: 21% Resolved: 79% Thean et al. (2001b)‏ 12-μ AGN 98 VLA-A (0”.25)‏ 87% (8.4 GHz)‏ Unresolved: 50% Slightly recolved: 20% Two components: 10% Linear: 20% Nagar et al. (2005)‏ Palomar Galaxies (96% LLAGN)‏ VLA: 197 VLBA+I: 44 VLA (0”.15)‏ VLBA (2-5 mas) Seyferts: 47% LINERS: 44% Transition: 16% Sub-pc scale jets: 45%

  30. “Frustrated jets” in Seyferts? Large fraction of Seyfert Galaxies have large-scale bipolar super-bubbles [Colbert et al. 1996a,b] (Cecil et al. 2001, 2002)‏ • Spectra of components A and B is similar to GPS spectra → regions of interactions between jet and dense external medium • Time evolution of radio continuum emission behave as expected for a jet interacting with a clumpy medium • Jet momentum spread in the interaction site may explain the bubbles (Saxton et al. 2005)‏ • Generalizing this scenario may explain why jets in Seyfert rarely propagate on kpc scales

  31. Interpretation of the fundamental plane Scale-invariant jets[Heinz & Sunyaev 2003] Radio luminosity scales with BH mass and accretion rate independently of the jet model Scaling depends on α, and the electron distribution index → on accretion physics only X-ray emission from BH accretion at a few percent Eddington is consistent with radiative inefficient flow only In low accretion rate sources, jet power is proportional to accretion power Challenges? Seyferts and LL RGs seem to follow different planes [Wang et al. 2006; Panessa et al. 2007] (Wang et al. 2006)‏

  32. Role of absorption (Ulvestad et al. 1999a)‏ (Ulvestad et al. 1999b)‏ Mkn348 • pc-scale double sources with brightness temperature 1010-11K → synchrotron emission • Historical variability → one sided-jet • One sideness → free-free absorption by ne≥2·105 cm-3 T≥8000 K (X-ray absorption) or ne≥107 cm-3 T≥ 106.6 K • [Exceptional sources: they more powerful than many 12μ sources, against the general correlation between radio power and size → jet starts very luminous and then decay, CSO/GPS link?]

  33. NLSy1 (Gallo et al. 2006)‏ (Komossa et al. 2006)‏ NLSy1 vs. GPS [Guainazzi et al. 2006; Vink et al. 2006] • ≤7% of NLSy1s are radio-loud (against 10-20% of “normal” Seyfert 1s)‏ • Stack of 19 VLA observations of undetected NLSy1 (R≤0.27)‏ • 5/6 radio-loud NLSy1 are GPS/CSS

  34. Bicknell´s (2002) argument L(O[III])≈1042 erg s-1 implies Ljet≈1044 erg s-1 for the same scale law as in GPS/CSS However, for standard radio power to jet luminosity conversion factors P5GHz≈1023 Jy implies Ljet≈1041 erg s-1 This implies that the electron to positron fraction is small (≈0.01)‏ Jets flows in Seyferts could start from the inner 10 gravitational radii as magnetically-driven winds Radio emerges from internal schoks in the plasma.

  35. LLAGN (LHα<1040 erg s-1)‏ (Nagar et al. 2005)‏ Correlation between sub-pc radio power and BH mass, galaxy luminositx • Main differences between LINERS and Seyfers • lower nuclear gas densities • lower accretion rate • more efficient in launching sub-pc scale jets • GBC analogy? • LINERS are in a "low/hard state" • Seyfert in a "high/soft" state

  36. Radio jet orientation (Kinney et al. 2000)‏ (Schmitt et al. 2001)‏ The distribution of angles between the radio jets and the galaxy disk is consistent with being random, provided that a galaxy is recognized as a Seyfert only if the angle between the jet and the l.o.s. is ≤40º [consistent with a basic assumption of the Seyfert unified scenarios] • Misalignment between the accretion disk and the host galaxy disk [also Ulvestad & Ho 2001]: • Feeding of a misaligned disk: warping by slef-irradiation instabilities, misaligned gravitational potential, nuclear star clusters, Bardeen-Petterson instabilities … • Misaliged inflow: minor mergers, capture of nuclear star clusters or individual molecular clouds …

  37. Unification scenario and radio emission • Seyfert 1s and 2s are indistinguishable in: • radio luminosity • radio size (Thean et al. 2001; also Ulvestad & Ho 2001)‏ • Oddities: • Sources with ionization cones host larger radio sources • Sources with hidden BLR are more radio powerful • observational bias?

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