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AGN; the answer is blowing in the wind

AGN; the answer is blowing in the wind. Nick Schurch. Chris Done, Malgorzata Sobolewska & Marek Gierlinski. 12 years ago, a galaxy far far away…. 2 years ago, a galaxy far far away…. Turner et al 1993; ROSAT and EXOSAT. Netzer et al 2003; XMM-Newton. AGN are complex.

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AGN; the answer is blowing in the wind

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  1. AGN; the answer is blowing in the wind Nick Schurch. Chris Done, Malgorzata Sobolewska & Marek Gierlinski.

  2. 12 years ago, a galaxy far far away… 2 years ago, a galaxy far far away… Turner et al 1993; ROSAT and EXOSAT Netzer et al 2003; XMM-Newton AGN are complex

  3. 12 years ago, a galaxy far far away… 2 years ago, a galaxy far far away… Marshall et al 1993; BBXRT Kinkhabwala et al 2004, Matt et al 2004; XMM-Newton AGN are complex

  4. Dynamical connections. • How do we fuel the central engine? • No obvious link between the accretion disk, BLR, NLR, Torus and galaxy. • Dynamical link MUST exist. Two problems

  5. Dynamical connections. • How do we fuel the central engine? • No obvious link between the accretion disk, BLR, NLR, Torus and galaxy. • Dynamical link MUST exist. • Spectral components… • Origin of most components ‘understood’; even if the details are not. • Continuum, accretion disk & neutral reflection, emission and absorption lines, cold and warm absorption etc. • Origin of the soft X-ray excess is not understood. • It could be the result of… • A separate spectral component (e.g. tail of thermal accretion disk emission), but… • Uniform ‘temperature’ indicative of an atomic origin. Page et al 2004 1H0707-495 Fabian et al 2004 Two problems

  6. Dynamical connections. • How do we fuel the central engine? • No obvious link between the accretion disk, BLR, NLR, Torus and galaxy. • Dynamical link MUST exist. • Spectral components… • Origin of most components ‘understood’; even if the details are not. • Continuum, accretion disk & neutral reflection, emission and absorption lines, cold and warm absorption etc. • Origin of the soft X-ray excess is not understood. • It could be the result of… • Reflection off the accretion disk (atomic, ionised & realivistically blurred) but… • Difficult to make enough reflected flux to explain the strongest soft excesses. Ross et al 2005 c Reflected soft X-ray flux  Continuum soft X-ray flux. Two problems

  7. Physically, a wind provides… • A simple dynamical link between the regions of the unified AGN. • A physical origin for the BLR and NLR. • Spectrally, a wind provides… • Multiple physical locations for ionised emission & absorption. • A simple explanation of the soft X-ray excess based on atomic physics. • An origin for the mess of complexity observed in detailed observations. Why is a wind an attractive idea?

  8. Our new picture looks like.. • Strongly accelerating wind (~0.1c) … • High-T, high-, very broad spectral features. • Difficult to distinguish from genuine continuum emission  Soft excess? • Fast wind (~103 km s-1)… • Broad features, easy to spot  BLR. • Slow wind (~102 km s-1) • Narrow features, easy to spot  NLR Why is a wind an attractive idea?

  9. etc… Winds are common in nature

  10. Mrk 78 NGC 4151 NGC 1068 Mrk 3 • AGN winds revealed in UV & X-ray observations of the NLR. • OIII images reveal bi-conical, clumpy structures • UV emission lines all blueshifted (~500 km s-1). • Chandra & XMM-Newton identified soft X-ray emission co-spatial with the UV ionization cones. • X-ray emission composed of many spectral lines (Si K, SiXIII OVII, OVIII, NeIX, NeX Lyman , MgXI). • X-ray lines all blueshifted (~1000 km s-1). • Wide range of lines  wide range of ionisation states  wide range of densities and/or pressures.. •  Clumpy, photoionised, outflowing material! AGN winds on large scales

  11. The wind is composed of photoionized gas. • Model emission & absorption from the photoionised gas with XSTAR • Lx=1044 erg s-1, =2.4,  =1012 cm-3, NH=1023 cm-2, log()=2.7, Cf=0.5 & Vturb=100 km s-1. • Include disk refection and galactic absorption… • Unrealistic model • No outflow velocity field Particularly important close in, where velocity gradient is high! • R << R Wind is thick! • Constant density gas Wind is likely to have very non- uniform density structure. R R Modelling winds: X-ray emission & absorption

  12. Gierlinski & Done 2004 • The wind will have an outflow velocity that is a function of radius. • Absorption, and emission, from gas moving at a wide range of velocities. • Close to the SMBH, gravitational effects will be important. • Simplest approximation is a Gaussian velocity distribution. • Previous work only treated the absorption, but … • Demonstrated that sufficiently broadened absorption, might reproduce the soft X-ray excess! • Can this remain the case when we include the emission? Modelling winds: The velocity field

  13. Vrad=0 – 0.2c, vrad=3000 km s-1 • The wind will have an outflow velocity that is a function of radius. • Absorption, and emission, from gas moving at a wide range of velocities. • Close to the SMBH, gravitational effects will be important. • Simplest approximation is a Gaussian velocity distribution. • Previous work only treated the absorption, but … • Demonstrated that sufficiently broadened absorption, might reproduce the soft X-ray excess! • Can this remain the case when we include the emission? • Yes… but the lines do fill in some of the absorption. Modelling winds: The velocity field

  14. The line emission normalization is given by: • Klines = Cf L38 DKpc-2 • Cf is the covering fraction of the material. • L38 is the intrinsic source luminosity, between 1-1000 Ryd in units of 1038. • DKpc is the source distance in Kpc. • Given an power-law form input continuum this becomes: • Klines = Cf Dkpc-2 (4Dcm2) KplE-+1dE • Kpl is the normalization of the input power-law •  is the power-law photon index • Distance dependence removed! • For a given , the Klines  Kpl & Cf. • Best-fit Klines, c.f. best-fit Kpl, tells us Cf. • Given Cf we can calculate M and Mtotal for the wind. 103 Ryd  1 Ryd c Hard to get any other way! • Consistency Check! • We expect: • MwindMedd • Mwind10-(12) M • Mtotal MBLR 10M . . . . . Modelling winds: How strong is the line emission?

  15. Bright (Vmag=14.38), nearby (z=0.089), Quasar (Lx~1044 erg s-1) & NLS1. Very strong soft excess! Can we spot the fast wind?: PG1211+143

  16. Bright (Vmag=14.38), nearby (z=0.089), Quasar (Lx~1044 erg s-1) & NLS1. • Very strong soft excess! • Complicated X-ray spectrum! • Thermal comptonization continuum • Complex absorption system, with multiple warm absorbers (Pounds et al 2003, Chartas et al 2003). • Ionised accretion disk reflection. Can we spot the fast wind?: PG1211+143

  17. Bright (Vmag=14.38), nearby (z=0.089), Quasar (Lx~1044 erg s-1) & NLS1. • Very strong soft excess! • Complicated X-ray spectrum! • Thermal comptonization continuum • Complex absorption system, with multiple warm absorbers (Pounds et al 2003, Chartas et al 2003). • Ionised accretion disk reflection. • We must be careful to get the continuum right! … Aside … Can we spot the fast wind?: PG1211+143

  18. Bright (Vmag=14.38), nearby (z=0.089), Quasar (Lx~1044 erg s-1) & NLS1. • Very strong soft excess! • Complicated X-ray spectrum! • Thermal comptonization continuum • Complex absorption system, with multiple warm absorbers (Pounds et al 2003, Chartas et al 2003). • Ionised accretion disk reflection. • We must be careful to get the continuum right! =1.55, no reflection, no complex absorption, Iron K edge, Eedge=7.3 keV. =1.79, no reflection, complex absorption, Iron XXVI Ly line. Eline=7.02 keV Can we spot the fast wind?: PG1211+143

  19. Bright (Vmag=14.38), nearby (z=0.089), Quasar (Lx~1044 erg s-1) & NLS1. • Very strong soft excess! • Complicated X-ray spectrum! • Thermal comptonization continuum • Complex absorption system, with multiple warm absorbers (Pounds et al 2003, Chartas et al 2003). • Ionised accretion disk reflection. • We must be careful to get the continuum right! Can we spot the fast wind?: PG1211+143

  20. Bright (Vmag=14.38), nearby (z=0.089), Quasar (Lx~1044 erg s-1) & NLS1. • Very strong soft excess! • Complicated X-ray spectrum! • Thermal comptonization continuum • Complex absorption system, with multiple warm absorbers (Pounds et al 2003, Chartas et al 2003). • Ionised accretion disk reflection. • We must be careful to get the continuum right! Can we spot the fast wind?: PG1211+143

  21. Bright (Vmag=14.38), nearby (z=0.089), Quasar (Lx~1044 erg s-1) & NLS1. • Very strong soft excess! • Complicated X-ray spectrum! • Thermal comptonization continuum • Complex absorption system, with multiple warm absorbers (Pounds et al 2003, Chartas et al 2003). • Ionised accretion disk reflection. • We must be careful to get the continuum right! • No BeppoSAX data. No Integral data. Poor XTE data. PG1211 is faint > 10keV! • 2-60 keV = 3! (Guinazzi et al 2000). • We know that NLS1s have steep X-ray continua! (Porquet et al 1999). Can we spot the fast wind?: PG1211+143

  22. Thermal Comptonization continuum. • Power-law,   2.4 • Accretion disk reflection. • Lx/Ld  0.5 • Min 0.2Medd • Rinn  20Rs • Two narrow, outflowing, absorption/emission systems. • log()  2, 3.3 • NH  1022, 1023 cm-2 • Small Cf (<0.1 upper limit) • Diskwind absorption/emission model. • log() = 2.74 • NH = 1.4x1023 cm-2 •  = 0.2c (0.186-0.22) • Cf  0.4 Modelling PG1211+143 . .

  23. Thermal Comptonization continuum. • Power-law,   2.4 • Accretion disk reflection. • Lx/Ld  0.5 • Min 0.2Medd • Rinn  20Rs • Two narrow, outflowing, absorption/emission systems. • log()  2, 3.3 • NH  1022, 1023 cm-2 • Small Cf (<0.1 upper limit) • Diskwind absorption/emission model. • log() = 2.74 • NH = 1.4x1023 cm-2 •  = 0.2c (0.186-0.22) • Cf  0.4 • 2 = 1013/948 d.o.f Modelling PG1211+143 .

  24. Log() = 2.66  3% NH = 1023 cm-2,  = 2,  = 0.2 Markowitz, Edelson & Vaughan 2003 • When we vary the ionisation parameter, the spectral shape changes. • RMS Variability has a VERY characteristic shape! • Do we see this characteristic shape in the observed RMS variability spectra of AGN? Even better…

  25. Log() = 2.66  3% NH = 1023 cm-2,  = 2,  = 0.2 Markowitz, Edelson & Vaughan 2003 • When we vary the ionisation parameter, the spectral shape changes. • RMS Variability has a VERY characteristic shape! • Do we see this characteristic shape in the observed RMS variability spectra of AGN? Even better…

  26. The Good: • Very good fit to complex data. • Completely reproduces the soft excess without separate components, or unreasonably strong reflection. • Smeared wind has a sensible(ish) range of velocities. (c.f. 24000 km s-1 lines & 50000 km s-1 lines – PDS 456) • Wind , NH also sensible. • Including emission lines gives sensible Cf. • The Bad: • How can we reconcile the wind with the other absorption/emission systems?… • outflowing at a single, slower, velocity & more ionised. (vout=25000 km s-1c.f. 60000 km s-1 log()=3.3 c.f. 2.7) • outflowing at a single, even slower, velocity & less ionised. (vout=12000 km s-1c.f. 60000 km s-1 log()=2.0 c.f. 2.7) • Other material represents the wind as it slows down far from the point of acceleration? • lower ionisation material = condensing phase? • higher ionisation material = expanding phase? • Maybe shocks can help us slow the wind down? . . . . • The Ugly: • Mwind1023 M X • Mwind>Medd>Min X • Mtotal >>MBLR X • The current model doesn’t work… but the idea might be right! • Could be telling us that.. • R ~ R •   constant • v(R)  Gaussian Does it really work?

  27. Run XSTAR on a thick slab. • Computationally intensive. • Run XSTAR with constant pressure approximation. • Bug in XSTAR 2.1kn3! • More computationally intensive than  = constant. • Use a more physical velocity field. • Use equations for velocity along a streamline. – Murray et al 1995 • Weight v(R) with (R). • Smear using this profile. Fixed! The next step: Version 1.

  28. Use info from simulations of a ‘reasonable’ AGN diskwind! • 108 M black hole. • M = 2 M yr-1 • Chop up simulation and choose l.o.s. • Read out information for each segment • , T, , vgrad 1, T1, 1, v1 The next step: Version 2… with a little help .

  29. Use info from simulations of a ‘reasonable’ AGN diskwind! • 108 M black hole. • M = 2 M yr-1 • Chop up simulation and choose l.o.s. • Read out information for each segment • , T, , vgrad • , T,  + simple continuum  XSTAR Power-law 1, T1, 1, v1 The next step: Version 2… with a little help The next step: Version 2… with a little help

  30. Use info from simulations of a ‘reasonable’ AGN diskwind! • 108 M black hole. • M = 2 M yr-1 • Chop up simulation and choose l.o.s. • Read out information for each segment • , T, , vgrad • , T,  + simple continuum  XSTAR • vgrad + XSTAR  smearing Power-law 1, T1, 1, v1 The next step: Version 2… with a little help

  31. Use info from simulations of a ‘reasonable’ AGN diskwind! • 108 M black hole. • M = 2 M yr-1 • Chop up simulation and choose l.o.s. • Read out information for each segment • , T, , vgrad • , T,  + simple continuum  XSTAR • vgrad + XSTAR  smearing • Use this spectrum as the continuum for the next segment the l.o.s passes through. 2, T2, 2, v2 The next step: Version 2… with a little help

  32. Use info from simulations of a ‘reasonable’ AGN diskwind! • 108 M black hole. • M = 2 M yr-1 • Chop up simulation and choose l.o.s. • Read out information for each segment • , T, , vgrad • , T,  + simple continuum  XSTAR • vgrad + XSTAR  smearing • Use this spectrum as the continuum for the next segment the l.o.s passes through. • Iterate over total l.o.s. i, Ti, i, vi The next step: Version 2… with a little help

  33. Use info from simulations of a ‘reasonable’ AGN diskwind! • 108 M black hole. • M = 2 M yr-1 • Chop up simulation and choose l.o.s. • Read out information for each segment • , T, , vgrad • , T,  + simple continuum  XSTAR • vgrad + XSTAR  smearing • Use this spectrum as the continuum for the next segment the l.o.s passes through. • Iterate over total l.o.s. • Instant disk wind spectrum with self consistent velocity smearing! i, Ti, i, vi The next step: Version 2… with a little help

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