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Thomas Boller Max-Planck-Institut für extraterrestrische Physik, Garching

AGN Science learned from previous missions: Issues for the coming decade. Thomas Boller Max-Planck-Institut für extraterrestrische Physik, Garching. (i) How to interprete the nature of the soft X-ray emission. (ii) Sharp spectral drops in the HE spectra of NLS1s.

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Thomas Boller Max-Planck-Institut für extraterrestrische Physik, Garching

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  1. AGN Science learned from previous missions: Issues for the coming decade Thomas Boller Max-Planck-Institut für extraterrestrische Physik, Garching

  2. (i) How to interprete the nature of the soft X-ray emission (ii) Sharp spectral drops in the HE spectra of NLS1s (iii) Single Thermal Comptonization (iv) Search for gravitativ redshifted X-ray/optical lines in BLR (v) Chemical abundances of the SB component (vi) Dark Matter determination via chemical abundances

  3. (i) How to interprete the nature of the soft X-ray emission Reflection spectrum interpretation or Thermal disc interpretation

  4. Reflection spectrum interpretation Thermal disc interpretation Boller 2002,3 Tanaka 2004 Gallo 2004 Fabian 2004 1H0707-495 Photons cm-2 s-1 keV-1 Energy [keV] Energy [keV] 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 surfaceBenefit of the reflection model is that the bumps in the soft energy band of 1H0707 can be naturally attributed to reflection as a complex Fe-L lines

  5. Assuming the Thermal disc interpretation is correct Physical relevant AGN parameters can be derived: BH Mass Eddingtion accretion rate (efficiency of accretion) Number of associated relations Eddington accretion rate versus spectral complexity Eddington accretion rate versus metallicity

  6. NLS1s BLS1s BLS1s LINERs Accretion-rates dependence on Black hole masses NLS1s • LINER • caveates: • - separate • nuclear • emission • following • Hagai´s comment: • if SLOAN people • are right, • LINERs • shift up LINERs

  7. Spectral complexity obtained via a simple power-law fit Present in Super-Eddington accretion rate objects

  8. Spectral complexity correlates with accretion rate fit in the 2-10 keV range LINERS often as a simple power-law NLS1s more complex - soft excess - spectral curvature - sharp spectral drops

  9. Metallicity dependence on the accretion rate 13224 with super-Eddington accretion Clear trend of FeII/Hb with accretion rate for NLS1 and high-z QSO Boller et al. 2003 Netzer et al. 2004 Fe overabundance 3-10 required in all NLS1s with sharp spectral drop, even for reflection dominated model optical Fe II emission increases with accretion rate

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

  11. The sharpness of the feature 1H0707-495 (2000)

  12. The (time-dependent) energy of the feature First detection of a sharp spectral drop was in 1H0707 at an energy of 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 Kb UTA absorption). This requires a huge mass and energy loss rate in the outflow, it remains uncertain how huge outflows can alter the appearence of the edge. The edge energy is difficult to explain in terms of reflection. Even in the most extreme light bending scenarios, it is difficult to achieve such a sharp feature at high energies of 8.2 keV (found in IRAS 13224).

  13. 1H0707-495 IRAS 13224-3809 8.2 keV 7.5 keV in 2002 Counts s-1 keV-1 7.1 keV in 2000 Energy [keV] Energy [keV] PCM: higher ionization (Fe VII-X, Fe XIX-XXIII) unlikely, missing Kb absorption high outflow v of 0.05 and 0.15 c required Details of the deep spectral drop:relevant for high accretion rates drop energy not always the same for 1H 0707, it strikingly it shifted from7.1 to 7.5 keV (>5 s) for IRAS 13224 is found even higher at8.2 keV RDM: energy shift due to different x

  14. Photoelectricabsorption X-ray reflection (light bending) Boller 2002,3 Tanaka 2004 Gallo 2004 1H0707-495 1H0707-495 Fabian 2002 Miniutti 2003 Fabian 2004 keV (keV cm-2 s-1 keV-1) Photons cm-2 s-1 keV-1 Energy [keV] Energy [keV] Counts s-1 keV-1 Counts s-1 keV-1 c2 ratio Energy [keV] Energy [keV] XMM-Newton cannot disentangle absorption from reflection

  15. 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 of three separate reflectors, which would result in blending out any distinct features The high-flux state (Leighly 2002) is realised by the emergence of the power-law component and minimasion of the reflection component. However, the soft excess was still dominated over the power-law, and the 1 keV bumps were still present, both should be significantly suppresed (and statistically insignifanct given the smaller collecting area of Chandra)

  16. Spectral Variability Significant spectral variability in 1H0707 and IRAS 13224 more significant in the 1-5 keV band Fabian 2004 showed that this can be explained by a variable PL, dominating the 1-5 keV band and less variable reflection <1 and > 5 keV Situation more complicated for the PC scenario a 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 during The reflection dominated low flux state. The opposite is observed in 1H0707! And: The detection of especially alternating lags, between various energy bands in IRAS 13224 is a serious challange for both models

  17. Reflextion model in different flux states flux high flux state power-law reflection component low flux state Energy [keV]

  18. Steepness of the soft and hard X-ray spectra The steeper continuum slopes in the 0.1-2.4 keV band may be more difficult to understand if the soft-excess is a reflection component rather than a thermal one. In addition: Both reflection and PC flatten the spectrum above, 2 keV, but NLS1s tend to show stepper hard X-ray slopes (Brandt 1997)

  19. Advantages from the simplied picture Both models, optically thick thermal emission and relativistically blurred emission 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 of other methods

  20. Spectral changes in dependence of the flux state In the high state, Fe K Linie is dimishing

  21. 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 LB will lead to quite different spectra The intrinsic X-ray spectrum is highly absorbed in the PC case, therefore Extreme variations of a_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)

  22. Issues for the coming decade XEUS simulations Reflection model fitted with thermal emission from the disc Thermal model fitted with ionized reflection from the disc

  23. (iii) Single Thermal Comptonization 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, but Hybrid thermal/non-thermal electron layers remain unconstrained

  24. The model XMM-Newton spectral fit Counts[s-1 keV-1] corona Photons [cm-2 s-1 keV-1] X-ray emission lines from SB IC Energy [keV] Energy [keV] Thermal Comptonisation in Mrk 110 Thermal comptonization gives a temperature of 60+-20 keV of the disc layer and the Compton parameter g is a function of the Photon index G. This means that it is not possible to solve for both the optical depth t and kT for the hot electron layer

  25. XEUS simulation show that kT of the hybrid layer, Lorentz factors,compactness and SB abundances parameters will be constrained 50 ks XEUS simulation Counts [s-1 keV-1] Energy [keV] 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

  26. Grav. red. X-ray linein the BLR (iv) Search for gravitativ redshifted X-ray/optical lines in BLR 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) eV O 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 x with thefollowing best fit parameters: E=(531.9+-0.2) eV R_in=(150-50+150) r_g R_out=(3000-1500+3000) r_g i=(31-5+4) dg Similar results obtained byCostantinie (2006) Consistent with calculations from A. Müller (XMM talk next week)

  27. (vi) Chemical abundances of the SB component Examples: NGC 6240 and Mrk 110 Element abundances not constrained vapec code does not find the abundances values for most of the elements AGN -Fe Ka in reflection -Highly absorbed PL component Starburst contribution 3 plasma- components kT = 0.7 keV Counts s-1 keV-1 10-3 10-2 10-1 kT = 1.4 keV NH = 1024 cm-2 kT = 5.5 keV Fe XXV,XXVI Data/Model 0 1 2 0.3 1.0 2.0 5.0 10 Energy [keV] (observers frame)

  28. The power of combining Chandra with XMM-Newton 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 0.5 1.5 5 10 keV Chandra image binned in energy according to XMM-Newton spectral results

  29. Alcaniz et al. 03 WL> 0.78 (vii) Dark Matter determination In addition to WMAP, eROSITA, SN, cluster measurementsWMand WL can also be constrained from element abundances of distant quasars 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

  30. (i) How to interprete the nature of the soft X-ray emission (ii) Sharp spectral drops in the HE spectra of NLS1s (iii) Single Thermal Comptonization (iv) Search for gravitativ redshifted X-ray/optical lines in BLR (v) Chemical abundances of the SB component (vi) Dark Matter determination via chemical abundances THE END - THANKS

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