AGNs: A Review Th. Boller Max-Planck-Institut fr extraterestrische - - PowerPoint PPT Presentation

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AGNs: A Review

• Th. Boller

Max-Planck-Institut für extraterestrische Physik, Garching Accreting black holes Fe Kα GR effects Fe Kα GR dynamics BH spin measurements 1H0707-495: spectral template and time lags The relativistic RM model: strong and weak field limit results

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Accreting BHs

Open questions: ESA CV 2015-2025 YB writing

• how does matter behave in the strong GR field regime?
• does it always obey GR predictions?
• what are the processes near the event horizon? (accretion/ejection)
• how does the spin affect the emission/jet processes?
• how are BH spins distributed? (BH birth/growth)

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previous Fe Kα line measurements

the accretion disc line interpretation for broad relativistic Fe Kα lines is robust in 8 AGNs robust against other models which can mimic a red wing (Reeves 2004)

• absorption by high column density
• high ionization warm absorbers
• continuum uncertainties

Nandra 2006, Fabian 2002 NGC 3516 NGC 4051 NGC 4151 Mrk 766 NGC 2992 NGC 3783 MGC 52316 MCG-6-30-15 MCG-6-30-15

Fe Kα GR effects

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Fe Kα GR dynamics

• I. Fe Kα time resolved and mean spectra

mean spectrum

Iwasawa04

data model NGC 3516

dynamics

emission from a single

• rbiting spot

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• II. Fe Kα on-phase, off-phase statistics

Variations of the red feature

Fe Kα GR dynamics

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• III. Predictions

ESA CV 2015-2025 YB strong gravity section

Fe Kα GR dynamics

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BH spin measurements

Why do we care about the BH spin?

• stellar mass BHs: - dynamics of BH formation in supernovae
• supermassive BHs: - propagate vs. retrograde accretion
• relative importance of mergers

and accretion modes

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BH spin measurements rely on the ISCO ≅ Rin

BH spin: GR predictions

ISCO = f(spin) relativistic line profile

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Early results in MCG-6

indicate that Rin < 2 Rg which translates into a BH spin of a > 0.94

Fabian02

BH spin measurements

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The relativistic Fe K line should be associated with a full X-ray reflection spectrum which shows up at > 10 keV (Compton hump)

Relativistic X-ray reflection and BH spin

Miniutti09

Swift J2127.4+5654 with Suzaku

Ross, Fabian05

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The relativistic RM accounts for the whole broadband spectrum to delivers the BH spin

Relativistic X-ray reflection and BH spin

Swift J2127.4+5654

Miniutti09

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Broad band relativistic RM analysis

a ~ 0 is excluded but just at the 3σ level a ~ 0.998 is excluded at more than 5σ intermediate spin due to a recent major merger?

Relativistic X-ray reflection and BH spin

Swift J2127.4+5654

(Miniutti09)

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This is an AGN belonging to the class of NLS1 galaxies (Puchnarewicz1992, Boller96 , Fabian09) it is remarkable in the X-rays: large amplitude and fast X-ray variability(Gallo04,Blustin09) huge soft X-ray excess extreme spectral curvature at Fe energies (Boller02) all these properties are observed in almost all (unobscured) AGN to a much lesser extent and therefore much more difficult to interpret presently

The special case of 1H 0707-495

• I. The extreme

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• ratios of the data to a simple power law + BB model
• two unambiguous features appear between 0.6-1 keV and 4-7 keV

and they can be interpreted as broad Fe L and K lines coming from the same medium with huge reflection fraction and high Fe abundance

The special case of 1H 0707-495

• II. spectral properties

time-averaged

• rbit by orbit

Fe L

Fe K

Fabian09

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Looking for time lags between lines and continuum: the most crucial result supporting the relativistic RM

fast variations (< 20 min)

The special case of 1H 0707-495

• III. Time lags

primary PL comes first followed by reflection component

30 min 30 seconds

Fabian09

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The observed lag means that:

• the soft X-ray spectrum (Fe L) has to be reprocessed emission
• if it was the same continuum the lag would be in the opposite direction
• the magnitude of the lag (~ 30s) is dictated by light travel time:
• the X-ray corona is very close to the BH (few RG)
• the BH mass is likely 3-5 x 106 Msun

The special case of 1H 0707-495

• III. Time lags

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It is a natural consequence of having a X-ray corona close to the BH as demonstrated by the ~30s lag

GR light bending

The special case of 1H 0707-495

• IV. Why is reflection so strong?

RG,X RG,Z

Miniutti,Fabian03

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The special case of 1H 0707-495

V: There is another template: IRAS 13224-3809

Pointi10

Also negative time lag detected but with lower statistics

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Do we have a spectral template ?

What a standard one would look like In the standard situation and with normal exposures we are unable to detect all these features except for the soft excess (which is indeed ubiquitously) detected

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The special case of 1H 0707-495

• VI. The relativistic RM for soft broad X-ray lines

Refl Refl+ kdblur ξ σ σ

(erg cm s-1) (eV) (eV)

5000 ~400 ~650 2000 200 400 1000 30 100 500 10 60 200 5 20 100 4 15

O VII/VIII blend O VIII blend Energy [keV] EFE [keV cm-2 s-1]

Ross, Fabian05 Boller10

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1H0707 strong and weaker field GR limit results

reflection: strong GR field limit Index=6.3+-0.4, Rin(G)=3.3+-0.1, ξ=1000+-260 emission from the innermost stable orbit strong Compton broadening

FWHM ~ 1/3c

additional soft broad line blends: weaker GR field limit emission from a few 1000 RG

FWHM ~ 0.03 – 0.08c Boller10

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RM parameters: Index=3.4+-0.6 Rin(G)=3.6+-0.4 ξ=6000+-900 E=0.60 σ=85 eV FWHM~1/3c E=0.95 keV σ=150 eV FWHM~1/3c

Reflection: strong GR field

Additional blends: weaker GR field FWHM 18000 km/s =0.06c 12000 km/s =0.04c

Ark 564 strong and weaker field GR limit results

Boller10

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Reflection: strong GR field

Index=3.1+-3.0 Rin(G)=3.4+-0.9 ξ=1400+-1000 E=0.53 σ=60 eV FWHM~0.1c E=0.90 σ=70 eV FWHM~0.08c Additional blend: weaker GR field FWHM 10000 km/s =0.003c

Mrk 110 strong and weaker field GR limit results

Boller10

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Predictions for IXO

• 1. this allows to test GR prediction via IXO measurements
• 2. the strong gravity Fe Kα measurements can be extended to the weaker field

limit by studying relativistic soft X-ray lines line profile measurements provide values for gcore which deliver the zG and RG

• =

i i i core

f f g g

distance RG gravitational redshift zG

Müller06

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The Future

satellites: eROSITA, ASTRO-H, ELT, LISA, IXO…..(Planck, Herschel) important impact on multifrequency observations and physics

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(Future) Great Observatories

Radio SKA mm ALMA IR JWST NIR Opt. EELT IXO X-ray

Maiolino08

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Are the GR prediction correct? First light: What is the nature of the earliest galaxies? What is the nature of the host galaxies of super-massive black holes and gamma ray bursts? What sources are responsible for reionisation? What is the metal enrichment history of galaxies and the IGM? How many types of matter exist? What is dark matter? types? What is dark energy? Does it evolve? How many types are there?

New science goals with MWL future

Arnaud et al. 08, Nandra10, ESA CV YB10