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Solving Quasars part I

Fermilab Colloqium 29 October 2003. Solving Quasars part I. in particular… Understanding Quasar Atmospheres. Martin Elvis Harvard-Smithsonian Center for Astrophysics. Elvis M., 2000, Astrophysical Journal 545, 63. Fermilab Colloqium 29 October 2003. Quasars * unsolved after 40 years.

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Solving Quasars part I

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  1. Fermilab Colloqium 29 October 2003 Solving Quasarspart I in particular… Understanding Quasar Atmospheres Martin Elvis Harvard-Smithsonian Center for Astrophysics Elvis M., 2000, Astrophysical Journal 545, 63

  2. Fermilab Colloqium 29 October 2003 Quasars* unsolved after 40 years Discovered in 1963 Quasars are the most powerful continuous radiation sources in the Universe Once were a `hot topic’ • Were the first to start the downfall of Steady State Cosmology • - via ‘evolution’: change in density with cosmic time • Now astronomers have moved on to easier problems • – Large scale structure, Dark Energy and Gamma-ray bursts • Quasar studies continue to generate many papers • …but little understanding? * Note for the pedantic: By ‘quasars’ I mean all types of ‘activity’ in galaxies

  3. Fermilab Colloqium 29 October 2003 What’s the problem? We have no images of a quasar atmosphere Would need 1000 times sharper pictures than Hubble or Chandra<100mas Must rely on spectra: span all wavelengths: X-ray - optical - radio • Enormousarray of detail • Superficial understanding

  4. Fermilab Colloqium 29 October 2003 Why Study Quasars? • We live on a planet • A star gives us life • Galaxies dominate the Universe • … but why do quasars matter? • Here are 4 answers:

  5. Fermilab Colloqium 29 October 2003 Radio Gamma-ray X-ray 1. An Astronomer’s Answer Outside the wavelength range that our eyes are sensitive to Quasars dominate the night sky

  6. Fermilab Colloqium 29 October 2003 Billions of times brighter than stars. Can outshine a whole galaxy Emit stronglyfrom radio to g-rays. How do they do that? Make galaxy length jets 2. An Astrophysicist’s Answer Gravity powered, not fusion. via Black Holes 106 - 109 as massive as the Sun. Gas heats up falling toward it, like a spacecraft on re-entry. The power available from gravity for heating is all too obvious following the Columbia tragedy

  7. Quasars lie at the hearts of galaxies: Galaxy mass and quasar black hole mass are tightly connected. Maggorrian et al, Ferrarese & Merritt, Gephardt et al. How? Should be governed by different processes. Emit up to 1/5 of power in Universe:Important input, may dominate in some places, times. Already exist at t<1Gyr(z=6) FIRST survey discovery, Becker et al. ½ Gyr from WMAP reionization at z=20 special role in early Universe? reionization, seeding galaxies… element creation, star formation catalyst via dust creation? 3. A Cosmologist’s Answer

  8. Fermilab Colloqium 29 October 2003 MCG -6-30-15 (XMM) Eject bulk gas at 99.50% speed of light G=10 similar to proton in Fermilab Tevatron 99.88%c Impacts gas of intergalactic medium.->what emerges? Accelerates e- to g~1000 -> TeV photons X-rays come from region of Strong Gravity seen in 6.4 keV `Fe-K’ (=Fe Lyman-a) emission line? Reynolds C. GR redshift? 6.4 keV Reynolds C. Wilms et al., 2002, MNRAS, 328, L27 4. A Physicist’s Answer

  9. Fermilab Colloqium 29 October 2003 What do we know? High level theory rapidly gave a clear picture massive black hole Lynden-Bell 1969 accretion disk Lynden-Bell 1969, Pringle & Rees 1972,Shakura & Sunyaev 1972 relativistic jet Rees 1967 [PhD], Blandford & Rees 1974 All established just 10 years after discovery

  10. Fermilab Colloqium 29 October 2003 This theory describes a naked quasar does not connect to the atomic physics features observed in quasars Leaves us with no way to order observations, nothing to test

  11. Fermilab Colloqium 29 October 2003 Atomic features in Quasar Atmospheres High ionization: e.g. CIV, OVI Low ionization: e.g. MgII, Hb. All studied separately with separate telescopes

  12. Whipple 10 meter Quasars have no temperature Compton gamma-ray Observatory Chandra Hubble MMT Sub-millimeter array VLA

  13. Fermilab Colloqium 29 October 2003 Wall, Tree, Rope, Spear, Snake, Fan Not having the complete picture can be misleading Blind men and the elephant. Manga VIII Hokusai, Katsushika (1760-1849)

  14. Fermilab Colloqium 29 October 2003 we need a ‘low theory’that deals with the multitude of quasar details These optically thin features are all interconnected S = `quasar atmosphere’ • Just as there are textbooks on ‘Stellar Atmospheres’ • we need the subject of ‘Quasar Atmospheres’ • Takes more than 1 step. • First build anobservational paradigm i.e. what do the observations drive require of any theory?

  15. Fermilab Colloqium 29 October 2003 Accelerating bi-conical wind Thin Vertical wind Supermassive black hole A Paradigm for Quasar Atmospheres Elvis M., 2000, Astrophysical Journal 545, 63 A Geometric & Kinematic solution c.f. Rees relativistic jets for blazars/radio sources Quasar Atmosphere hollow cone Broad Absorption Lines no absorption lines NB: Independent of Unification Jets are not included Reflection features Narrow absorption lines Accretion disk X-ray `warm’ absorbers Broad Emission Lines X-ray/UV ionizing continuum Can now re-construct this model using data not in Elvis 2000

  16. Princeton AGN Physics with the SDSS, 29 July 2003 NSTX at PPPL National Spherical Torus eXperiment Princeton Plasma Physics Laboratory Take a lesson from lab plasmas: use all the data 2mm interferometer X-ray PHA X-ray crystal spectrometer Radiometer Thomson scattering Far infrared tangential Interferometer/polarimeter Visible spectrometer Vacuum UV survey spectrometer  NSTX diagnostic instruments cover everything Grazing incidence spectrometer Tangential bolometer array Single channel visible Bremsstrahlung detector Polarimeter X-ray pinhole camera Soft X-ray arrays Fast tangential X-ray camera Reflectometer array Infrared cameras

  17. Fermilab Colloqium 29 October 2003 12,277 Papers on Quasars since 1963**ADS to 4/18/03, refereed only , search on abstract containing ‘quasar’ | ‘AGN’ 1/day. Now 2 per day = 5% of all astronomy papers Spam! • Need filters--- • Physical measurements Mass, length, density. Not ratios, column densities • Favor absorption:advice from Steve Kahn c.1985 1-D spatial integral, not 3-D; blueshift = outflow • Use Polarization Non-spherical geometry • With these filters just a dozen papers define the structure of quasar atmospheres.

  18. Fermilab Colloqium 29 October 2003 Peterson & Wandel 2000 ApJ 540, L13 Mass Doppler width of em. Line Keplerian orbits Light echo delay (days) 1.Physical Measurements: BEL Velocity-radius relation Reverberation mapping shows Keplerian velocity relation in BELs ~1000 rs, Schwartzchild radii Pole-on Broad Emission Lines close to Keplerian velocities

  19. Fermilab Colloqium 29 October 2003 FAST Edge-on Pole-on Relativistic beaming Continuum/Haflux Flat disk continuum isotropic SLOW Rokaki et al. 2003 astro-ph/0301405 1.Physical Measurements:Angle Use VLBI + X-ray to get angle of jet toline of sightRokaki et al. 2003astroph/0301405 • Rotation about jet axis • c.f. Wills & Browne 1986, Brotherton 1996, McLure & Jarvis 2003 • Ha polarization rotation also implies orbiting gas Smith et al 2002 (2) Continuum drops as cos q EW=EW0[1/3 cosq(1+2cosq)]-1 limb darkened disk Ha does not Ha scale height larger than disklike optical continuum But BLR is rotating rotating cylinder? A highly non-equilibrium shape Pole-on Simplest solution: BLR is in a rotating wind

  20. Princeton AGN Physics with the SDSS, 29 July 2003 new Chandra HETG: 900ksec NGC3783 new Narrow X-ray lines new Same Outflow ~1000 km s-1 2. Absorption Features Winds are common in quasars Narrow UV lines High ionization OVII,OVIII High ionization CIV, OVI Outflow ~1000 km s-1 Seen in same 50% of quasars Seen in 50% of quasars Simplest solution: Same gas, 2 phases

  21. Fermilab Colloqium 29 October 2003 2. Absorption: More Physics from X-rays Chandra HETGS 850ksec spectrum of NGC 3783 Krongold, Nicastro, Brickhouse, Elvis, Liedahl & Mathur, 2003 ApJ, in press. astro-ph/0306460 Over 100 absorption features fitted by a 6 parameter model One T~106 K and one T~104 K, in pressure balance to 5% 2-phase gas in pressure equilibrium

  22. Fermilab Colloqium 29 October 2003 2. Absorption: where is the wind? Arav, Korista & de Kool 2002, ApJ 566, 699 Arav, Korista, de Kool, Junkkarinen & Begelman 1999 ApJ 516, 27 • Velocity dependent covering factors • Absorber isclose to continuum source •  absorber is moving transverse Wind is close to continuum, crosses line of sight

  23. Fermilab Colloqium 29 October 2003 A quasar wind is like a flame We are lookingthrough a flow Apparent lack of change is a common handicap for astronomers the ‘Static Illusion’ e.g. expansion of the Universe, cluster cooling flows, quasar disks

  24. Fermilab Colloqium 29 October 2003 Emission lines: a thin wind? Leighly & Moore 2003, ApJ submitted • Narrow Line Seyfert 1 galaxies (NLSy1s) show broad, strongly blueshifted high ionization (CIV) lines • Understandable as disk wind • redshifted lines hidden by disk • Low ionization lines from outer disk c.f. Collin-Souffrin, Hameury & Joly,1988 A&A 205, 19 See: Gaskell 1982 Wilkes 1984 Low ionization MgII BELs are rotating, transverse, thin winds

  25. Fermilab Colloqium 29 October 2003 wind To Earth Black hole accretion disk R DR 2. Absorption / 1. Physical Measurements:Wind Density,thickness X-ray continuum Nicastro et al. 1999 ApJ, 512, 184 UV/X-ray absorption responds to continuum changes: photoionized time “OVII edge” • But responds with a delay • = recombination/ionization time •  density ne~108 cm- 3 for OVIII • ne~3x107 cm-3 for FeXVII “OVIII edge” Absorbing wind is dense density + column density (~3x1022 cm-2) thickness (~1015 cm) < distance to continuum Absorbing wind is narrow

  26. Fermilab Colloqium 29 October 2003 3. Polarization: X-ray absorbers Leighly et al. 1997 ApJ 489, L137 Absorption line quasars are highly polarized in optical: 1. Scattering off non-spherical distribution Edge-on structure 2. Pole-on objects must be unobscured  scatterer & obscurer: flattened & co-axial Absorbers are seen edge-on

  27. Princeton AGN Physics with the SDSS, 29 July 2003 Flattened, Transverse Wind  axisymmetry Mathur, Elvis & Wilkes 1995 ApJ, 452, 230 A transverse wind suggests an axisymetric geometry: bi-cones • looking edge-on see absorbers • Wind does not hug disk • pole-on: no absorbers •  absorbers in all quasars Absorbing wind is a bi-cone to 1st order

  28. Fermilab Colloqium 29 October 2003 Similar Temperatures For low U absorber, BELs new Putting X-ray/UV absorber and BEL together Elvis 2000 ApJ 545, 63; Krongold et al. 2003 Both are disk winds rising well above the disk plane They share physical properties: Similar Radius: for NGC 5548 r( abs ) ~1015 - 1018cm recomb. time + NHX r(BELR)~1016cm CIVreverberation mapping Similar Pressure: P( abs ) ~1015 = 104 K x 1011 cm-3 P(BELR)~1015 = 106 K x 109 cm-3 Matching Ionization Parameter, U: T/U( abs ) = 106 = T( abs ) ~106 K/ U( abs ) ~1 T/U(BELR)= 106 = T( abs ) ~104 K/ U(BELR) 0.04 Keep it simple: Emission and Absorption are 2 phases of the same quasar wind

  29. Fermilab Colloqium 29 October 2003 Components of Quasar Atmospheres High ionization: e.g. CIV, OVI Low ionization: e.g. MgII, Hb. United In a 2-phase transverse wind in pressure balance

  30. Fermilab Colloqium 29 October 2003 The Final Element:Broad Absorption Lines (BALs) 10% of quasars show BALs with doppler widths ~2%c - 10%c ~10x NALs. Clear acceleration (or deceleration) Ferland & Hamann 1999 Annual Reviews of Astronomy & Astrophysics , 37, 487 Old question: Special objects? or Special angle?

  31. Princeton AGN Physics with the SDSS, 29 July 2003 Broad Absorption Lines (BALs) Lee & Turnshek 1995 ApJ 453 L61 • BEL FWHM correlates with BAL velocity (at minimum flux) • V(BAL) ~ 2 FWHM(BEL) 2:1 More BEL-BAL correlations: Reichard et al. 2003 BEL width BAL width BAL gas knows about BEL gas

  32. Fermilab Colloqium 29 October 2003 Detachment velocity flux Continuum Em. line BAL wavelength BALs from a rotating wind Hall et al. 2002 ApJS, 141, 267 • Redshifted BAL onset • Possible occasionally in a rotation dominated wind blue red BALs need a rotating wind … like the BELs

  33. Fermilab Colloqium 29 October 2003 Ogle, PhD thesis, 1998 3. Polarization: BAL troughs Ogle et al. 1999 ApJS, 125, 1; Ogle 1998 PhD thesis, CalTech BAL troughs are highly polarized –scattered light off flattened structure => BALs are common. Universal? Scattering solves other BAL problems:ionization,abundances, NH Thomson thick:X-ray Fe-K, Compton hump Hamann 1998 ApJ 500, 798; Telfer et al. 1998 ApJ 509, 132 Is the BAL wind itself the scatterer? Bi-cone model Predicts distribution of non-BAL quasar polarization Conical wind fits BALs well

  34. Fermilab Colloqium 29 October 2003 MKN 509 Polarized light 2 x width total light 3. Polarization: VBELR Young et al. 1999 MNRAS 303, 227 If BALs are cones, all quasars should have BAL gas • Supported by observations: • Emission lines twice as broad in polarized, non-variable light. •  non-BAL quasars have Thomson thick gas at large, BAL, velocities • Don’t see in absorption because out of our line of sight • Large scattering region • (but not too large, Smith et al. 2003 MNRAS) • with BAL velocities BAL velocity gas exists in non-BAL quasars

  35. Fermilab Colloqium 29 October 2003 Detachment velocity flux Continuum Em. line BAL wavelength One last, crucial, complication Angles are wrong: BAL velocities too high: ~10,000 km s-1 10 times narrow absorption lines Requires extreme cone opening angle. Simple solution:bend wind Predicts: 1. ‘detached BALs’* = Lowest velocity where wind bends into our line of sight = vertical velocity from disk 2. ~10% covering factor dr at r gives 6o divergence angle radiation forces gas to diverge Both previously unexplained *Could this be an ionization effect? Dv a IP?

  36. Fermilab Colloqium 29 October 2003 60deg: broad absorption lines 20 deg: no absorption lines Quasar Atmospheres, Quasar Winds One geometry unites all the features High ionization Broad emission lines Low ionization 85 deg: narrow absorption lines

  37. Fermilab Colloqium 29 October 2003 Components of Quasar Atmospheres Thompson thick BAL scatterer must also make Compton hump, Fe-K High ionization: e.g. CIV, OVI Low ionization: e.g. MgII, Hb. All atomic features now included

  38. Fermilab Colloqium 29 October 2003 Accelerating bi-conical wind Thin quasi-vertical wind Supermassive black hole Accretion disk X-ray/UV ionizing continuum Putting it all togetherinformationfilters worked efficiently! BALs hollow cone Polarization no absorption lines BELs WAs NALs Elvis M., 2000, ApJ, 545, 63

  39. Fermilab Colloqium 29 October 2003 Blind men and the elephant. Manga VIII Hokusai, Katsushika (1760-1849) Hokusai never saw a live Elephant Not bad – not 100% right – but gets the idea This picture of quasar atmospheres is probably in much the same state: needs physics bones

  40. Fermilab Colloqium 29 October 2003 A Quasar Observational Paradigm Disk Winds:tie together all the pieces of thequasar atmosphere • Explains features not ‘built in’ BAL covering factor; detachment velocity, Hi ionization BEL blueshifts. • Survived testsX-ray absorber outflow v, 2-phase UV/X-ray absorber, pressure balance • Makes predictions High ionization BEL, X/UV absorber radii, thickness are equal • Creates a research programc.f. Lakatos 1980 • Allows tractable physics exploration… • Work BACK to origin in accretion disk physics • Work OUT to impact on surroundings Can begin to build a ‘low’ theory of quasar atmospheres

  41. Fermilab Colloqium 29 October 2003 Krongold, Nicastro, Brickhouse, Elvis, Liedahl & Mathur, 2003 low theory: 2-phase equilibrium Krolik, McKee & Tarter 1981, ApJ, 249, 422 • Photoionized gas tends to have phases • Not really new: • Does not work for a static medium • so abandoned…. a mistake! • Works fine in a wind.dynamic • Equilibrium determined solely by: SED & ionization thresholds • Should be similar from object to object • No need to assume ‘clouds’

  42. new Fermilab Colloqium 29 October 2003 Krongold, Nicastro, Brickhouse, Elvis, Liedahl & Mathur, 2003 low theory: accretion disk physics, II Krongold et al. in preparation • ~106K phase depends critically on SED Nicastro 1999, Reynolds & Fabian 1995 • Use absorber (T,x) to determine unseeable EUV SED • -> Test models of accretion disk • inner edge ill-defined- boundary condition • ‘plunging region’Krolik et al. Reynolds & Fabian 1995MNRAS 273 116

  43. new Fermilab Colloqium 29 October 2003 Wind Middle wind escapes No wind Inner: `failed wind’ Outer: wind falls back • Note: L>LEdd quasars always have winds • See King & Pounds 2003 astro-ph/0305571 • Reeves et al … ;Chartas et al… weakness Some BALs are L>LEdd winds low theory: Why is the wind thin? Risaliti & Elvis 2003, ApJ submitted • Intermediate level 2D theory • Wind driven by UV absorption lines • c.f. O-star winds, CAK • ignore gas pressure • 3 Zones: Inner, Middle, Outer • 1. Inner: over-ionized • Only Compton scattering - insufficient • shields gas further out from X-rays = Murray & Chiang `hitchhiking gas’ • 2. Middle:UV absorption drives gas •  wind escapes • 3. Outer: shielded from UV, weak initial push from local disk radiation – wind falls back density

  44. Princeton AGN Physics with the SDSS, 29 July 2003 Cooling BEL clouds Cooling BEL clouds Oxygen rich dust Carbon rich dust Looking Out: quasars as dust factories Elvis, Marengo & Karovska, 2002 ApJ, 567, L107 • Outflowing BEL gas expands and cools adiabatically • BEL adiabats track through dust formation zone of AGB stars Applies to Carbon-rich and Oxygen-rich grains • Outflows rates ~10 Msol/yr at • L~1047 erg/s •  0.1 Msol/yr of dust • assuming dust/gas ratio of Long Period Variables •  >107Msol over 108 yr outburst lifetime • Metallicity super-solar even in z=6 BELs • High Z/Zsol should enhance dust production • Larger dust masses likely

  45. Princeton AGN Physics with the SDSS, 29 July 2003 Looking Out: quasars & starbursts Elvis, King et al., in preparation • Conventionally, starbursts fuel quasar outbursts • What if it is the other way around? • All Quasars have winds • Quasar wind outflow rates ~1 Msol/yr at L~1046 erg/s •  shocks on host galaxy ISM • induces starburst • Fuels AGN • Wind … cycle of AGN/starburst activity?

  46. Fermilab Colloqium 29 October 2003 Quasar Atmospheres, Quasar Winds Good Observational Paradigm: Quasar Atmospheres are dynamic Thin, rotating, funnel-shaped disk wind Low Theory beginnings: 2 phase medium Line driven winds Prospects: Use quasar atmospheres for accretion disk physics Dust creation at high z Quasar to Starburst causality

  47. Fermilab Colloqium 29 October 2003 Sizes are implicit in: Peterson et al. 1999 ApJL 520, 659. Kaspi et al. 2001 ApJ 533, 631 Postscript: Imaging Quasars What we really want is to look at quasar atmospheres At low z sizes are~0.1mas Elvis & Karovska, 2002 ApJ, 581, L67 • Resolvable with planned ground interferometers • VLT-I, Ohana • Ideal telescopes: • Image the wind in space and velocity • 5 km-10 km IR 2mm interferometer at ‘Dome C’ in Antartica • ½-1km UV space interferometer • = NASA ‘Stellar Imager’ • Quasar community should push for “Quasi-Stellar Imager” SOLVE QUASAR ATMOSPHERES No more fancy indirect deductions!

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