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Joint formation and evolution of SMBHs and their host galaxies:

Joint formation and evolution of SMBHs and their host galaxies:. How do the Quasar-Spheroid correlations change with the Cosmic Time?. Marzia Labita. A. Treves Università dell’Insubria, Como, Italy R. Falomo INAF, Osservatorio Astronomico di Padova, Italy

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Joint formation and evolution of SMBHs and their host galaxies:

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  1. Joint formation and evolution of SMBHs and their host galaxies: How do the Quasar-Spheroid correlations change with the Cosmic Time? Marzia Labita A. TrevesUniversità dell’Insubria, Como, Italy R. FalomoINAF, Osservatorio Astronomico di Padova, Italy R. DecarliUniversità dell’Insubria, Como, Italy J. KotilainenTuorla Observatory, Piikkio, Finland M. UslenghiINAF-IASF, Milano, Italy

  2. SMBHs and host galaxies • Most (if not all) nearby (early type) galaxies host a supermassive black hole (SMBH) at their centers - proper motion of stars (Milky Way) - rotation curves of gas clouds – MASER (22 objects) • The host galaxies of low redshift quasars contain a massive spheroidal component (observative results: see Dunlop et al. 2003, Pagani et al. 2003…) Elliptical galaxies ↔ SMBHs QSOs and their host galaxies

  3. Joint formation of SMBHs and massive spheroids • According to the hierarchical merging scenario, massive spheroids should be the products of successive merging events • At low redshift, the central BH mass is strongly correlated to the properties of the host galaxy bulge (of both active and inactive galaxies) …OUTSIDE THE SPHERE OF INFLUENCE! Formation of Formation and fuelling Elliptical galaxies of their active nuclei QSOs and their host galaxies

  4. Quasar: • Nuclear luminosity • Radio power (RLQ – RQQ) • Spectral shape BH mass determination and evolution Host Galaxy: • Bulge luminosity • (Stellar velocity dispersion, morphology, size) Host galaxy luminosity (mass) evolution Quasar – Host Galaxy connection: • Study the BH – host mass correlation at low z and trace its cosmological evolution close and beyond the peak of the quasar activity QSOs and their host galaxies

  5. Quasar: • Nuclear luminosity • Radio power (RLQ – RQQ) • Spectral shape BH mass determination and evolution Host Galaxy: • Bulge luminosity • (Stellar velocity dispersion, morphology, size) Host galaxy luminosity (mass) evolution Quasar – Host Galaxy connection: • Study the BH – host mass correlation at low z and trace its cosmological evolution close and beyond the peak of the quasar activity QSOs and their host galaxies

  6. The NIR to UV continuum of radio loud (RL) vs. radio quiet (RQ) quasarsM. Labita, A. Treves, R. Falomo, 2007, MNRAS, in press (astro-ph/0710.5035) Understanding the nuclear engine of quasars: • Characterization of the Spectral Energy Distribution (SED) • Distinction between RLQs and RQQs in the Unified Models of AGN (relativistic jet, BH spin?) …compare and contrast the SEDs of RLQs and RQQs QSOs and their host galaxies

  7. First step: QSO sample selection Requirements: • Sample as large as possible • Minimally biassed against the radio properties and the nuclear color of the QSOs • Observations in multiple bands (from NIR to UV) to construct the SED • Radio detection (RLQs vs. RQQs) • Negligible host galaxy component • SDSS quasar catalogue (u, g, r, i, z) • 2MASS detection (J, H, K) • FIRST observation area (20 cm flux) QSOs and their host galaxies

  8. Distinction between RLQs and RQQs • 91% of the objects are below the FIRST limit RLQ if radio to optical flux ratio >10; RQQ otherwise • We choose g<18.9, so that we can discriminate between RLQs and RQQs Host galaxy contribution • Host luminosity estimate based on radio power and redshift We require that host to nuclear flux ratio <0.2 QSOs and their host galaxies

  9. The final sample • 887 QSOs (774 RQQs and 113 RLQs) R band absolute magnitude redshift QSOs and their host galaxies

  10. SED construction • For each object, 8 datapoints log ν – log (νLv) from the u, g, r, i, z, J, H, K observations • Construction of the restframe SEDs of single objects • Normalization of the RLQs and RQQs subsamples at 1014.8 Hz • Construction of the average spectral energy distributions QSOs and their host galaxies

  11. Average SEDs of RLQs and RQQs • RLQs are more luminous and redder than RQQs • Huge dispersion of the spectral indices POWER LAW FIT log(vLv) relative log(vLv) erg/s RLQs ALL RQQs log(v) Hz log(v) Hz QSOs and their host galaxies

  12. Color difference between RLQs & RQQs • RLQs are redder than RQQs in the NIR to UV region with Δα = 0.2 • P(KS)>99% • Redshift independence • Luminosity independence (L – z matched samples) RLQs RQQs Spectral index QSOs and their host galaxies

  13. SED shape: a possible bias • Request of 2MASS observation: only redder objects at high z • Both the SEDs result softer for high z objects (i.e. at high frequencies) • Let’s use 2MASS data only at low z! QSOs and their host galaxies

  14. Interpretation of the color difference • Is there an enhanced dust extinction in RLQs? • Difference of the thermal components? Big blue bump: superposition of black body emission from an accretion disc Color difference ↔ Temperature difference • Is there a real temperature difference? • Is the color difference related to spinning? • Difference of the non-thermal components? Is there synchrotron contamination from the relativistic jets in RLQs? QSOs and their host galaxies

  15. 1. Is there an enhanced dust extinction in RLQs? • ΔAV=0.16mag would explain the difference • Why RLQs are more extinted? • Different inclinations? • Dust production related to radio emission? QSOs and their host galaxies

  16. 2. Is there a real temperature difference? • Tdisk÷MBH-1/4 • BHs of RLQs are supposedly more massive • RQQs are expected to be hotter (and bluer) 3. Is the color difference related to spinning? • Radio emission is usually ascribed to faster spinning • Spinning BHs (RLQs) have a shorter last stable orbit radius and then a hotter disk → NO! QSOs and their host galaxies

  17. 4. Is there synchrotron contamination from the relativistic jets in RLQs? • In pole-on radio sources there is a significant chance of synchrotron contamination from the relativistic jets • Radio selected samples suffer from a bias towards pole-on radio sources (relativistic beaming) but in our sample does not! →The color difference between RLQs and RQQs is probably due to a real temperature difference of the accretion disks. NEXT STEP: quantify this effect! QSOs and their host galaxies

  18. Quasar: • Nuclear luminosity • Radio power (RLQ – RQQ) • Spectral shape BH mass determination and evolution Host Galaxy: • Bulge luminosity • (Stellar velocity dispersion, morphology, size) Host galaxy luminosity (mass) evolution Quasar – Host Galaxy connection: • Study the BH – host mass correlation at low z and trace its cosmological evolution close and beyond the peak of the quasar activity QSOs and their host galaxies

  19. First step: BH mass determinations at low z Dynamical BH mass determinations: VIRIAL THEOREM • Local Universe: stars orbiting around the SMBH →only inactive galaxies • Higher redshift: gas regions emitting the broad lines – BLR→Type I AGN! v = f∙ line-width (Doppler Effect) UV? Optical? f = ? R ÷ λ Lλα(from reverberation mapping) FWHM? σ-line? QSOs and their host galaxies

  20. Hβ broad emission of low-redshift quasars: Virial mass determination and the geometrical factor(Decarli R., Labita M., Treves A., Falomo R., 2007, submitted to MNRAS) AIM Solid base at low z to study nuclear-host connection beyond the peak of the nuclear activity (see also Labita et al. 2006, MNRAS, 373, 551) • Are BH mass determinations from Hβ and from CIV consistent? • Which is the better estimator? • FWHM or σ-line?  SOLID RECEIPT FOR BH MASS DETERMINATION  HINTS ON THE BLR GEOMETRY • Do the known correlations between the properties of QSOs and their host galaxies hold up to z~0.5? QSOs and their host galaxies

  21. The Sample • Quasars, z<0.7, reliable host galaxy luminosity determination, elliptical galaxy About 40 quasars at <z>~0.3 of which: 25 ASIAGO dedicated observations UV 29 HST archive spectra 9 2 9 0 12 SDSS catalogue spectra optical QSOs and their host galaxies

  22. Data reduction, measurements and analysis • Standard IRAF procedure • Subtraction of the FeII contamination (zero-order correction) • Monochromatic luminosity measurement (power-law fit) • Line-width measurements: • Narrow component subtraction • 2-gaussian fit of the broad component • FWHM and σ-line measurements: σ-line is strongly dependent on the line wings… QSOs and their host galaxies

  23. CIV vs. Hβ: line shapes and line-widths • Hβ profile is more “gaussian” (isotropic case) than CIV • R(Hβ)~1.5 R(CIV) but FWHM(Hβ)>FWHM(CIV) • The geometries of the Hβ and CIV regions are intrinsically different QSOs and their host galaxies

  24. BH mass – host luminosity correlation • CIV mass estimates are well correlated with MR • Hβ mass estimates are barely correlated with MR • CIV line-width is a better velocity estimator than Hβ • We can constrain f by matching the mass estimates via the BH mass – host luminosity correlation • NO redshift dependence of this correlation QSOs and their host galaxies

  25. BH mass – host luminosity correlation • CIV mass estimates are well correlated with MR • Hβ mass estimates are barely correlated with MR • CIV line-width is a better velocity estimator than Hβ • We can constrain f by matching the mass estimates via the BH mass – host luminosity correlation • NO redshift dependence of this correlation QSOs and their host galaxies

  26. Hints on the BLR geometry • Isotropic model f=√3/2: ruled out • Thin disc model f(θmin, θmax): ok for CIV clouds • For Hβ clouds? • Hβ shape • R vs. FWHM • Expected angles • Isotropic component + disc component • Thick disc model QSOs and their host galaxies

  27. The next step: QSOs at higher z • Spectroscopical campaigns (ESO, TNG, NOT…) are going on to collect the spectra of QSOs with a reliable bulge magnitude estimate • In the meantime… ESO 3.6m+EFOSC2 QSOs and their host galaxies

  28. Quasar: • Nuclear luminosity • Radio power (RLQ – RQQ) • Spectral shape BH mass determination and evolution Host Galaxy: • Bulge luminosity • (Stellar velocity dispersion, morphology, size) Host galaxy luminosity (mass) evolution Quasar – Host Galaxy connection: • Study the BH – host mass correlation at low z and trace its cosmological evolution close and beyond the peak of the quasar activity PRELIMINARY! QSOs and their host galaxies

  29. z~2.5 z~1.5 z~0.3 x x BH – bulge mass correlation: evolution with z Γ=MBH/Mbulge log MBH log Γ x MR redshift QSOs and their host galaxies

  30. z~2.5 z~1.5 z~0.3 x x BH – bulge mass correlation: evolution with z Γ=MBH/Mbulge log MBH log Γ x MR redshift QSOs and their host galaxies

  31. z~2.5 z~1.5 z~0.3 x x BH – bulge mass correlation: evolution with z Γ=MBH/Mbulge log MBH log Γ x Γ grows with z  ? MR redshift QSOs and their host galaxies

  32. Quasar: • Nuclear luminosity • Radio power (RLQ – RQQ) • Spectral shape BH mass determination and evolution Host Galaxy: • Bulge luminosity • (Stellar velocity dispersion, morphology, size) Host galaxy luminosity (mass) evolution PRELIMINARY! Quasar – Host Galaxy connection: • Study the BH – host mass correlation at low z and trace its cosmological evolution close and beyond the peak of the quasar activity QSOs and their host galaxies

  33. Host galaxy luminosity (mass) evolution x x QSOs and their host galaxies

  34. Host galaxy luminosity (mass) evolution x x QSOs and their host galaxies

  35. Host galaxy luminosity (mass) evolution x x ? Hint: at z~2.5 (peak of the nuclear activity), well formed BHs are hosted by not completely formed galaxies QSOs and their host galaxies

  36. Summary and conclusions (I) The NIR to UV continuum of RLQs vs. RQQs For a sample of ~1000 objects with SDSS – 2MASS observations: • Average SED construction • RLQs are more luminous than RQQs • RLQs are redder than RQQs and this is independent on redshift or luminosity • RQQs seem to be hotter due to smaller BH masses (???) FUTURE: Try to understand better why RLQs are redder than RQQs QSOs and their host galaxies

  37. Summary and conclusions (II) Joint formation and evolution of galaxies and SMBHs LOW REDSHIFT • Receipt for BH mass determination • Known correlations between BH – host mass hold up to z~0.5 Labita M., Falomo R., Treves A., Uslenghi M., 2006, MNRAS, 373, 551 Decarli R., Labita M., Treves A., Falomo R., 2007, submitted to MNRAS HIGH REDSHIFT • Host luminosity (mass?) SEEMS to increases with Cosmic Time (???) Kotilainen J., Falomo R., Labita M, Treves A., Uslenghi M., 2007, ApJ, 660, 1039 • Γ SEEMS to decrease with Cosmic Time (???) • Hint: at z~2.5 (peak of the nuclear activity), well formed BHs are hosted by not completely formed galaxies (???) FUTURE:What will the new observations at higher redshift tell us? QSOs and their host galaxies

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