Solving Quasars part I

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Solving Quasarspart I
Fermilab Colloqium 29 October 2003
in particular Understanding Quasar Atmospheres
Martin Elvis Harvard-Smithsonian Center for
Astrophysics
Elvis M., 2000, Astrophysical Journal 545, 63
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Quasars unsolved after 40 years
Fermilab Colloqium 29 October 2003
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
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Whats the problem?
Fermilab Colloqium 29 October 2003
We have no images of a quasar atmosphere Would
need 1000 times sharper pictures than Hubble or
Chandra lt100mas
Must rely on spectra span all wavelengths
X-ray - optical - radio

• Enormous array of detail

• ?Superficial understanding

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Why Study Quasars?
Fermilab Colloqium 29 October 2003

• We live on a planet
• A star gives us life
• Galaxies dominate the Universe
• but why do quasars matter?
• Here are 4 answers

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Fermilab Colloqium 29 October 2003
1. An Astronomers Answer
Outside the wavelength range that our eyes are
sensitive to

Quasars dominate the night sky
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2. An Astrophysicists Answer
Fermilab Colloqium 29 October 2003

• 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
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3. A Cosmologists Answer
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4. A Physicists Answer
Fermilab Colloqium 29 October 2003
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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
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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
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Atomic features in Quasar Atmospheres
Fermilab Colloqium 29 October 2003
High ionization e.g. CIV, OVI Low ionization
e.g. MgII, Hb.
All studied separately with separate telescopes
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Quasars have no temperature
Whipple 10 meter
Compton gamma-ray Observatory
Chandra
Hubble
MMT
Sub-millimeter array
VLA
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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)
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we need a low theory that deals with the
multitude of quasar details
Fermilab Colloqium 29 October 2003
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 an observational paradigm
• i.e. what do the observations drive require of
  any theory?

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A Paradigm for Quasar Atmospheres
Fermilab Colloqium 29 October 2003
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
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Take a lesson from lab plasmas use all the data
Princeton AGN Physics with the SDSS, 29 July 2003
2mm interferometer X-ray PHA X-ray crystal
spectrometer Radiometer Thomson scattering Far
infrared tangential Interferometer/polarimeter Vis
ible spectrometer Vacuum UV survey spectrometer

• ? NSTX diagnostic instruments cover everything

Grazing incidence spectrometer Tangential
bolometer array Single channel visible Bremsstrahl
ung detector Polarimeter X-ray pinhole
camera Soft X-ray arrays Fast tangential X-ray
camera Reflectometer array Infrared cameras
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12,277 Papers on Quasars since 1963 ADS to
4/18/03, refereed only , search on abstract
containing quasar AGN
Fermilab Colloqium 29 October 2003

• 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.

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1.Physical Measurements BEL Velocity-radius
relation
Fermilab Colloqium 29 October 2003

• Reverberation mapping shows Keplerian velocity
  relation in BELs

1000 rs, Schwartzchild radii
Pole-on
Broad Emission Lines close to Keplerian velocities
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1.Physical Measurements Angle
Fermilab Colloqium 29 October 2003
Use VLBI X-ray to get angle of jet to line of
sight Rokaki et al. 2003 astroph/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 EWEW01/3
cosq(12cosq)-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
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2. Absorption Features
Princeton AGN Physics with the SDSS, 29 July 2003
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
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Chandra HETGS 850ksec spectrum of NGC 3783
Fermilab Colloqium 29 October 2003
2. Absorption More Physics from X-rays
Krongold, Nicastro, Brickhouse, Elvis, Liedahl
Mathur, 2003 ApJ, in press. astro-ph/0306460

• Over 100 absorption features fitted by a 6
  parameter model
• ? One T106 K and one T104 K, in pressure
  balance to 5

2-phase gas in pressure equilibrium
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Fermilab Colloqium 29 October 2003
2. Absorption Pressure Balance
Krongold, Nicastro, Brickhouse, Elvis, Liedahl
Mathur, 2003 ApJ, in press. astro-ph/0306460
NGC 3783 Chandra HETG(MEG) spectrum solution
Free parameters in blue
If at same distance

2-phase gas in pressure equilibrium
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2. Absorption where is the wind?
Fermilab Colloqium 29 October 2003
Arav, Korista de Kool 2002, ApJ 566, 699 Arav,
Korista, de Kool, Junkkarinen Begelman 1999 ApJ
516, 27

• Velocity dependent covering factors
• ? Absorber is close to continuum source
• ? absorber is moving transverse

Wind is close to continuum, crosses line of sight
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A quasar wind is like a flame
Fermilab Colloqium 29 October 2003
We are looking through 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
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Emission lines a thin wind?
Fermilab Colloqium 29 October 2003
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 AA 205, 19

See Gaskell 1982 Wilkes 1984
Low ionization MgII
BELs are rotating, transverse, thin winds
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2. Absorption / 1. Physical MeasurementsWind
Density,thickness
Fermilab Colloqium 29 October 2003
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 ? ne108 cm- 3 for OVIII
• ne3x107 cm-3 for FeXVII

OVIII edge
Absorbing wind is dense
density column density (3x1022 cm-2) ?
thickness (1015 cm) lt distance to continuum
Absorbing wind is narrow
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3. Polarization X-ray absorbers
Fermilab Colloqium 29 October 2003
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
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Flattened, Transverse Wind ? axisymmetry
Princeton AGN Physics with the SDSS, 29 July 2003
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
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Putting X-ray/UV absorber and BEL together
Fermilab Colloqium 29 October 2003
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 CIV reverberation 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
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Components of Quasar Atmospheres
Fermilab Colloqium 29 October 2003
High ionization e.g. CIV, OVI Low ionization
e.g. MgII, Hb.
United
In a 2-phase transverse wind in pressure balance
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The Final ElementBroad Absorption Lines (BALs)
Fermilab Colloqium 29 October 2003
10 of quasars show BALs with doppler widths
2c - 10c 10x NALs. Clear acceleration (or
deceleration)
Ferland Hamann 1999 Annual Reviews of
Astronomy Astrophysics , 37, 487
Old question Special objects? or Special angle?
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Broad Absorption Lines (BALs)
Princeton AGN Physics with the SDSS, 29 July 2003
Lee Turnshek 1995 ApJ 453 L61

• BEL FWHM correlates with BAL velocity (at minimum
  flux)
• V(BAL) 2 FWHM(BEL)

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More BEL-BAL correlations Reichard et al. 2003
BEL width
BAL width
BAL gas knows about BEL gas
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BALs from a rotating wind
Fermilab Colloqium 29 October 2003
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
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3. Polarization BAL troughs
Fermilab Colloqium 29 October 2003
Ogle et al. 1999 ApJS, 125, 1 Ogle 1998 PhD
thesis, CalTech
BAL troughs are highly polarized scattered
light off flattened structure gt 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
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3. Polarization VBELR
Fermilab Colloqium 29 October 2003
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
• Dont 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
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One last, crucial, complication
Fermilab Colloqium 29 October 2003

• 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?
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Quasar Atmospheres, Quasar Winds
Fermilab Colloqium 29 October 2003
One geometry unites all the features
High ionization Broad emission lines Low
ionization
85 deg narrow absorption lines
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Components of Quasar Atmospheres
Fermilab Colloqium 29 October 2003
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
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Putting it all togetherinformation filters
worked efficiently!
Fermilab Colloqium 29 October 2003
BALs
hollow cone
Polarization
no absorption lines
BELs
WAs
NALs
Elvis M., 2000, ApJ, 545, 63
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Fermilab Colloqium 29 October 2003
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
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A Quasar Observational Paradigm
Fermilab Colloqium 29 October 2003

• Disk Winds tie together all the pieces of the
  quasar atmosphere
• Explains features not built in
• BAL covering factor detachment velocity, Hi
  ionization BEL blueshifts.
• Survived tests X-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 program c.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
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low theory 2-phase equilibrium
Fermilab Colloqium 29 October 2003
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

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low theory accretion disk physics, II
new
Fermilab Colloqium 29 October 2003
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
• -gt Test models of accretion disk
• inner edge ill-defined- boundary condition
• plunging region Krolik et al.

Reynolds Fabian 1995 MNRAS 273 116
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low theory Why is the wind thin?
new
Fermilab Colloqium 29 October 2003
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
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Looking Out quasars as dust factories
Princeton AGN Physics with the SDSS, 29 July 2003
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
• L1047 erg/s
• ? 0.1 Msol/yr of dust
• assuming dust/gas ratio of Long Period Variables
• ? gt107Msol over 108 yr outburst lifetime
• Metallicity super-solar even in z6 BELs
• High Z/Zsol should enhance dust production
• Larger dust masses likely

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Looking Out quasars starbursts
Princeton AGN Physics with the SDSS, 29 July 2003
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 L1046
  erg/s
• ? shocks on host galaxy ISM
• induces starburst
• Fuels AGN
• Wind
• cycle of AGN/starburst activity?

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low theory accretion disk physics, I
Fermilab Colloqium 29 October 2003
Risaliti et al., in preparation

• Wind is sensitive to initial vertical velocity
• Thickness of wind depends on density emissivity
  profile of disk
• How far can disk deviate from
• Shakura-Sunyaev r -15/8 law?
• Constrain viscosity generation, e.g. MRI
  magneto-rotational instability (Balbus Hawley)

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Quasar Atmospheres, Quasar Winds
Fermilab Colloqium 29 October 2003
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
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Postscript Imaging Quasars
Fermilab Colloqium 29 October 2003
What we really want is to look at quasar
atmospheres
At low z sizes are 0.1 mas
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!