thomas boller max-planck-institut für extraterrestrische physik, garching

Thomas BollerMax-Planck-Institut für extraterrestrische Physik, Garching

AGN Science learned from previous missions:Issues for the coming decade

2 Present and future AGN science issues Thomas Boller, MPE Garching

Tokyo workshop 2006

(i) How to interprete the nature of the soft X-ray emission

(ii) Sharp spectral drops in the HE spectra of NLS1s

(v) Chemical abundances of the SB component

(vi) Dark Matter determination via chemical abundances

(iii) Single Thermal Comptonization

(iv) Search for gravitativ redshifted X-ray/optical lines in BLR


Tokyo workshop 2006


Reflection spectrum interpretation

or

Thermal disc interpretation


Tokyo workshop 2006

Energy [keV]

1H0707-495 Boller 2002,3Tanaka 2004Gallo 2004

Phot

ons

cm-2 s

-1 k

eV-1

Thermal disc interpretation

The high T can be recovered by considering super-Eddington accretion

Rather uniform shape of the soft-excess

a characteristic T of about 120 eV emerges, the spread inT is small, however the L in samples span three orders of mag. This is not simple to understand in terms of any existing accretion disc theories.

Ross & Fabian suggest that the soft-excess is explained by blurred emission lines and bremsstrahlung from the hot disc surface

Benefit of the reflection model is that the bumps in the soft energy band of 1H0707 can be naturally attributed toreflection as a complex Fe-L lines

Energy [keV]

Reflection spectrum interpretation

Fabian 2004


Tokyo workshop 2006

Assuming the Thermal disc interpretation is correct

Physical relevant AGN parameters can be derived:

BH MassEddingtion accretion rate (efficiency of accretion)

Number of associated relations

Eddington accretion rate versus spectral complexityEddington accretion rate versus metallicity


Tokyo workshop 2006

Accretion-rates dependence on Black hole masses

NLS1s

BLS1s

NLS1s

LINERs

BLS1s

LINERs

LINERcaveates:

- separate nuclear emission

-following Hagai´s comment: if SLOAN people are right, LINERs shift up


Tokyo workshop 2006

Spectral complexity obtained via a simple power-law fit

Present in Super-Eddingtonaccretion rate objects


Tokyo workshop 2006

fit in the 2-10 keV range

LINERS often as a simple power-law

NLS1s more complex - soft excess - spectral curvature - sharp spectral drops

Spectral complexity correlates with accretion rate


Tokyo workshop 2006

Metallicity dependence on the accretion rate

13224 with super-Eddington accretion

Fe overabundance 3-10 required in all NLS1s with sharp spectral drop, even for reflection dominated model

Boller et al. 2003 Netzer et al. 2004

Clear trend of FeII/H with accretion rate for NLS1 and high-z QSO

optical Fe II emission increases withaccretion rate


Tokyo workshop 2006


The sharpness of the feature - most fundamental discriminator between thermal and reflection models -feature always sharp (<150 eV, resolution of the EPIC pn detector) in case of neutral absorption, whereas it will be broader in the line interpretation

- The measurements can rule out high photoionization,but is still not sufficient to exclude either partial covering or reflection, though it becomes a concerning for reflection


Tokyo workshop 2006

The sharpness of the feature

1H0707-495 (2000)


Tokyo workshop 2006

The (time-dependent) energy of the feature

First detection of a sharp spectral drop was in 1H0707 at an energyof 7.1 +-0.1 keV, perhaps coincidently, entirely consistent with the neutral Fe edge

However, it was the last time that an edge was detected at this energy.

The second observation of 1H0707 found the edge at 7.5 keV.

It appears unlikely that the edges are ionised, since there are no traces in the spectra for increased ionisation (e.g. no broading of the edge, no KUTA absorption).This requires a huge mass and energy loss rate in the outflow, it remains uncertain how huge outflows can alter the appearence of theedge.

The edge energy is difficult to explain in terms of reflection. Even inthe most extreme light bending scenarios, it is difficult to achieve sucha sharp feature at high energies of 8.2 keV (found in IRAS 13224).


Tokyo workshop 2006

Details of the deep spectral drop:relevant for high accretion rates

drop energy not always the samefor 1H 0707, it strikingly it shifted from 7.1 to 7.5 keV (>5 )for IRAS 13224 is found even higher at 8.2 keV

PCM: higher ionization (Fe VII-X, Fe XIX-XXIII) unlikely, missing K absorption high outflow v of 0.05 and 0.15 c required

RDM: energy shift due to different

IRAS 13224-3809

8.2 keV

Energy [keV]

1H0707-495

7.1 keV in 2000

7.5 keV in 2002

Energy [keV]

Cou

nts

s-1 k

eV-1


Tokyo workshop 2006

XMM-Newton cannot disentangle absorption from reflection

Photoelectric absorption

1H0707-495 Boller 2002,3Tanaka 2004Gallo 2004

Energy [keV]

Phot

ons

cm-2 s

-1 k

eV-1

Energy [keV]

Cou

nts

s-1 k

eV-1

X-ray reflection (light bending)

1H0707-495 Fabian 2002Miniutti 2003Fabian 2004

keV

(keV

cm

-2 s

-1 k

eV-1)

Energy [keV]

Cou

nts

s-1 k

eV-1

Energy [keV]

ratio


Tokyo workshop 2006

Drawbacks from the simplified picture

Reflection: when reflection dominates the 1 keV bumps would be most prominent when the source is the low state, and then should diminish as the power-law components emerges however, the 1 keV feature were not al all visible during the low state observations in 2000

According to Fabian 2002 the spectrum was a contrived mixture ofthree separate reflectors, which would result in blending out anydistinct features

The high-flux state (Leighly 2002) is realised by the emergence of thepower-law component and minimasion of the reflection component. However, the soft excess was still dominated over the power-law, andthe 1 keV bumps were still present, both should be significantly suppresed(and statistically insignifanct given the smaller collecting area of Chandra)


Tokyo workshop 2006

Spectral Variability

Significant spectral variability in 1H0707 and IRAS 13224more significant in the 1-5 keV band

Fabian 2004 showed that this can be explained by a variable PL, dominatingthe 1-5 keV band and less variable reflection <1 and > 5 keV

Situation more complicated for the PC scenarioa DOUBLE PC is required to explain the situation

Another point of concern:The amplitude of the variations.In the light bending model the variability should be depressed duringThe reflection dominated low flux state.The opposite is observed in 1H0707!

And:The detection of especially alternating lags, between various energybands in IRAS 13224 is a serious challange for both models


Tokyo workshop 2006

Reflextion model in different flux states

Energy [keV]

flux

low flux state

high flux statepower-lawreflection component


Tokyo workshop 2006

Steepness of the soft and hard X-ray spectra

The steeper continuum slopes in the 0.1-2.4 keV band may be moredifficult to understand if the soft-excess is a reflection componentrather than a thermal one.

In addition:Both reflection and PC flatten the spectrum above, 2 keV, butNLS1s tend to show stepper hard X-ray slopes (Brandt 1997)


Tokyo workshop 2006

Advantages from the simplied picture

Both models, optically thick thermal emission and relativistically blurredemission result in statistically acceptable fits with XMM-Newton

The Fe K line is diminishing when the flux is increasing (reflection adv.)

The column density increases when the flux is decreasing (bbody adv.)

If the soft excess is thermal and the partial covering model is correct,BH Masses and BH Growth rates can be determined, independent ofother methods


Tokyo workshop 2006

Spectral changes in dependence of the flux state

In the high state, Fe K Linie is dimishing


Tokyo workshop 2006

Alternatives to waiting 10 years for XEUS

High-quality XMM-Newton observations of NLS1s in different flux states should distinguish between the models (300 ks), as PC and LBwill lead to quite different spectra

The intrinsic X-ray spectrum is highly absorbed in the PC case, thereforeExtreme variations of _ox could be an indicator of PC

IRAS 13224 and 1H0707 are extreme, but not unique.As such, there shoud be many more similar objects (in progress)


Tokyo workshop 2006

Issues for the coming decadeXEUS simulations

Reflection model fitted with thermal emission from the disc

Thermal model fitted with ionizedreflection from the disc


Tokyo workshop 2006


Hot accretion disc e-1 layers produce via inverse Comptonisation power-law spectral distribution

Examples: TonS 180, Mrk 110

Second power-law required as a consequence of inverse Compton scattering of an hot electron layer above the accretion disc

Single thermal comptonization can be well constrained with XMM-Newton, butHybrid thermal/non-thermal electron layers remain unconstrained


Tokyo workshop 2006

Thermal Comptonisation in Mrk 110

Thermal comptonization gives a temperature of 60+-20 keV of the disc layer and the Compton parameter is a function of the Photon index .

This means that it is not possible to solve for both the optical depth and kT for the hot electron layer

The model

X-ray emission lines from SB

IC

corona

Energy [keV]

Ph

oto

ns [

cm

-2 s

-1 k

eV

-1]

XMM-Newton spectral fit

Energy [keV]

Cou

nts

[ s

-1 k

eV

-1]


Tokyo workshop 2006

Hybrid thermal/nonthermal electron distribution

Not constrained with the present XMM-Newton statistics

Lorentz factors, soft compactness and non-thermal compactness parameters cannot be uniquiqly determined with the present statistics

XEUS simulation show that kT of the hybrid layer, Lorentz factors,compactness and SB abundances parameters will be constrained

50 ks XEUS simulation

Energy [keV]

Counts

[s-

1 k

eV

-1]


Tokyo workshop 2006

Broad O VII triplet in Mrk 110 (Boller, Balestra 06)

Oxygen triplet

O VII ( r ) E=(572.5-0.3+0.4) eV O VII ( i ) E=(568.1-0.7+0.4) eVO VII ( f ) E=(561.9-0.4+0.8) eV

Broad component

E = (554.0-3.0+2.0) eV

THE DISPLACEMENT OF THE BROAD LINE WITH RESPECT TO THE MEAN VALUE OF THE 3 OXYGEN LINES IS 566.9-554.0 =12.9 eV CORRESPONDING TO z = 0.0228, FWHM ~9000 km s-1

Opitcal lines from Kollatschny do have smaller FWHM and smaller z

A fit with a relativistic profile gives the same with thefollowing best fit parameters:

E=(531.9+-0.2) eVR_in=(150-50

+150) r_gR_out=(3000-1500

+3000) r_gi=(31-5

+4) dg

Grav. red. X-ray linein the BLR

Similar results obtained byCostantinie (2006)

Consistent with calculations fromA. Müller (XMM talk next week)



Tokyo workshop 2006

(vi) Chemical abundances of the SB componentExamples: NGC 6240 and Mrk 110Element abundances not constrainedvapec code does not find the abundances values for most of the elements

0.3 1.0 2.0 5.0 10 Energy [keV] (observers frame)

C

ount

s s-1

keV

-1

10-3

10-2

10-1

D

ata /

Mod

el0

1

2

kT = 0.7 keV

kT = 1.4 keV

kT = 5.5 keVFe XXV,XXVI

NH = 1024 cm-2

AGN-Fe Ka in reflection-Highly absorbed PL component

Starburst contribution3 plasma-components


Tokyo workshop 2006

The power of combining Chandra with XMM-Newton

0.5 1.5 5 10 keV

T-gradient NH-gradient [keV] [cm-2]RED 0.5-1.5 0.2 1022 YELLOW 1.5-5.0 0.4 1022

WHITE 5.0-10.0 4.1 1022

Chandra image binned in energy according to XMM-Newton spectral results


Tokyo workshop 2006

(vii) Dark Matter determination

In addition to WMAP, eROSITA, SN, cluster measurements and can also be constrained from element abundances ofdistant quasars

> 0.78

Alcaniz et al. 03

Detection of a 2-Gyr-old quasar at z=3.91 (Hasinger et al. 2003) is of particularly interest as it constrains the amount of dark energy


Tokyo workshop 2006



(v) Chemical abundances of the SB component

(vi) Dark Matter determination via chemical abundances



THE END - THANKS

thomas boller max-planck-institut für extraterrestrische physik, garching

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