P.Coppi, Yale

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AGN à la Blandford , cont. [ What Worked, What Didn’t, and What Next? ]. ?. P.Coppi, Yale. What’s a Blandford, à la Google:. Kid’s definition. Dr. Roger Blandford Astrophysicist - PowerPoint PPT Presentation

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P.Coppi, Yale

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AGN à la Blandford, cont. [ What Worked, What Didn’t, and What Next? ]

What’s a Blandford, à la Google:

Kid’s definition

Dr. Roger BlandfordAstrophysicist

His research interests include: black holes, those famous supermassive space objects that gobble up matter and light; "gravitational lensing," which refers to the way light travels in curved paths around stars and galaxies; high-energy waves from space known as gamma ray bursts; the dim class of stars known as white dwarfs; and the structure and evolution of the universe.[pbs.org]

AGN à la Blandford, ca. 1986, IAUS

Mkn 421

Mkn 421

GeV Blazars…

EGRET

Pian et al. 1998

Gaidos et al. 1996

Fossati et al. 2002

One of the biggestsurprises!

TeV Blazars…

PKS 2155, ~5 min variability

Another superluminal jet source

…oops … it’s in our galaxy!

A “boring” object in the sky: the nearby elliptical galaxy M87

Optical

Radio“FEAST vs. FAMINE”A starved black hole…..

D. Harris,2003

M87 jet is not wimpy!!!

X-ray variability seen in HST-1 knot too!!

GX339 - Corbel et al. 2004 AGN !? - Maccarone et al. 2003

ADIOS: The X-ray/Radio correlation …

Another major development: arcsecond X-ray Imaging

CDF-S

When you can see with X-rays, again black holes much more common!

CDF-N/GOODS 2Msec(!) Chandra

The “M- Relation” (Ferrarese & Merritt, see also Gebhardt et al.)

Guess what: our black holeis not special!

Every big galaxy has one !

Finally some answers? Rare long-lived AGN vs. many short-lived AGN? Seems to be tilting decisively towards

relation,

( many relic SMBH)

X-ray/2MASS counts

( many active AGN missed optically)

No more Soltan/ problem?

M

M

Also, relation BH and galaxy know about each other!?

Galaxy & BH formation same process?

(Once correct for obscuration, redshift evolution s

M

imilar?)

Mergers/gas are clearly important in at least AGN phase.

FEEDBACK??? Even “low energy” astronomers can’t ignore black holes…

Blandford was right…. While LCDM appears correct, Both galaxy and AGN formation do seem to be anti-hiearchical (kind of) …

At z=2, massive elliptical progenitors COMPACT and this one may have σ ~500 km/sec!!

The “Feasting Objects” (FSRQ): interesting probes?

Eagerly await Fermi results on n(z),but in meantime have SWIFT/BATsurvey: see Ajello et al. 2009 ….

Old (pre-CGRO) view of gamma-ray Universe.

My model for thepre-CGRO sources…

The transitionfrom a non-thermalto a thermal pairplasma…

Coppi 1998

Johnson et al., 1994 …. There goes the thesis….

After CGRO…

EGRET Blazars and gamma-spheres:

Compilation by A. Zdziarski

Even though pairs may not be dominant, that pair plasma code was good for something ….

Chandra

??

Spectra of this quality generally do not exist for AGN!

Possible AGN spectral “states” not well-sampled!

What if you don’t have broad band data – X-ray binary example…

What’s E_cut => no idea what reflection spectrum to expect !

No broad band data = big uncertainties!

Ecut =900 kev, R=0.5,

Ecut =100 kev, R=1,

PEXRIV

OSSE

BAT

RXTE PCA

kTe = 68 keV,R = 0.4, = 1.8

kTe = 85 keV,R = 1.0, = 1.3(green)

Fitting only <20 keV or >50 keV leaves big uncertainty in predictions for other half of spectrum. Even with great statistics, an X-ray mission that only measured spectrum 20-150 keV allows a factor two uncertainty in reflection fraction!

Your line fit is only as good as yourcontinuum fit/model!

Chandra

??

Spectra of this quality generally do not exist for AGN!

Possible AGN spectral “states” not well-sampled!

Risaliti et al. 2002, BeppoSAX survey of Compton-thin Seyfert 2’s (NH~ 1022 – 1024 ) …

Red dots - measuredvalues

Black dots – lower limits

Contrary to what is assumedin XRB model fits, there is a large scatter in high energyspectra of AGN (both in power law index and high-energy cutoff).

~30% of objects haveE_C > 400 keV, which isNOT obviously compatiblewith XRB shape …

Typical (single)value assumedfor XRB models…

[N.B. The objects shown are a large fraction of the existingsample of AGN withgood HX spectra! ]

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In fact, we are just starting to see tip of iceberg in terms of possible AGN spectra!

Our view of the black hole universe is still highly biased….

The Super-Antennae, IRAS 19254 (Braito et al., 2009, Suzaku)

Even if the unabsorbed spectrum did not vary (unlikely), we know the environment varies. Details like the exact geometry of the absorber matter, especially in the Compton thick (NH > 1024) case, and may depend on host type, redshift, etc. This complication is largely ignored in current XRB models – we need broadband measurements of many objects to disentangle intrinsic vs. extrinsic (absorber-induced) variations!

Sample theoretical calculation (Monte Carlo, exact) --

Lines of sight

Geometry of obscuring material –a sphere. with an empty conical hole, andpossible paths of photons.

Spectrum on axis (black), perpendicular to axis (green), and on edge of obscuring material (red), and spectrum of source (dashed), for an opening of 30% of surface area, NH=1.0E25 and EC=300 KeV.

Different obscuration geometries imply different polarization signatures.

X-ray/gamma-ray polarimetry difficult but very useful! Disentangles geometryand emission

components.

Degree of polarization perpendicular to axis (green) and on edge of obscuring material (red) – same parameters as above.

On cosmic train wrecks, feasting, and the formation of black holes…

How do we make quasars at z>6!?

Multi-scale simulation by Mayer et al. 2009

Don’t ignore that gas!

Escala et al. 2004

LISA: gravitational waves!

Sensitivity best for LOWER mass (MBH<106 Mo) mergers!

Escala 2008

Origin of M-sigma relation?

Fueling-limitedscenario!

ENZO AMR simulationincluding star formationand accretion onto“large” central black holeparticle --

who needs a seed black hole?

1 arc sec

Where are the black holes??

Radio

X-Ray

Max et al. 2007, Science

Keck Adaptive Optics2.2 micron

NGC 6240

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[Sorry ]