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Revision of Blazars’ Nature Objects with Binary Supermassive Black Hole Ba š ta , M.

Revision of Blazars’ Nature Objects with Binary Supermassive Black Hole Ba š ta , M. Astronomical Institute, Academy of Sciences of the Czech Republic Supervisor: RNDr. R. Hudec, CSc. (ASU AV, CR) Consultant: doc. A. Sillanpaa (Tuorla, Finland). Hello everyone, welcome to my lecture.

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Revision of Blazars’ Nature Objects with Binary Supermassive Black Hole Ba š ta , M.

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  1. Revision of Blazars’ Nature Objects with Binary Supermassive Black Hole Bašta, M. Astronomical Institute, Academy of Sciences of the Czech Republic Supervisor: RNDr. R. Hudec, CSc. (ASU AV, CR) Consultant: doc. A. Sillanpaa (Tuorla, Finland) Hello everyone, welcome to my lecture Seminar of the Astronomuical Institute

  2. Outline of this lecture • What AGN and blazars are • What basic properties of blazars are • About our blazar sample for which we suggest supermassive binary black hole should be present • How we probe the binary nature of blazars and explain the observed behavior I will tell you . . . At first, let us talk about Active galactic nuclei (=AGN). We will see that blazars are just a class of AGN. Seminar of the Astronomuical Institute

  3. Active Galactic Nuclei (= AGN) in pictures Blazar Mkn 421 Quasar 3C 273 Seyfert galaxy NGC5194 Radio galaxy Centaurus A Seminar of the Astronomuical Institute

  4. Active Galactic Nuclei (= AGN) Active Galactic Nuclei (AGN) powerful luminosity; non-stellar spectrum; high variability; BH engine; differ in luminosity, spectra, variability, morphology; 1 - 10 % of galaxies supposed to be AGN Observational classification of AGN • QuasarsQuasi stellar radio sources, powerful, radio loud vs. quiet • Blazars Highly variable • Radio galaxies Powerful in radio, radio lobes, elliptical • Seyfert galaxies Spiral, luminous center, SG I vs. SG II • LINERs, Nuclear HII Regions Specific energy production • Strong IRAS & starburst galaxies Star formation Seminar of the Astronomuical Institute

  5. Engine of AGN & AGN Unification I Dusty torus Black hole + Accretion disk Radio lobes Coming closer to AGN Cygnus A Blazar 3C 273 Centaurus A Decreasing the angle between observer and jet Seminar of the Astronomuical Institute

  6. Engine of AGN & AGN Unification II Quasar Blazar Radio galaxy Seyfert 2 galaxy Radio loud (strong jets) vs. Radio quiet (weak jets) Torus Black hole + Accretion disk Seyfert 1 galaxy Jet !!! Antonucci, 1993 Seminar of the Astronomuical Institute

  7. Blazars & their powerful jet Jet = Beam of energetic particles and magnetic field moving close to the speed of light!! Supermassive black hole with accretion disc • Effects of the small angle between observer and jet: • Featureless continuum • Relativistic beaming • High luminosity • Superluminal motion • Gamma rays • Rapid variability Line of sight Blazar observer Seminar of the Astronomuical Institute

  8. Standard model of blazar = one supermassive black hole According to the Unification model (Antonucci, 1993) there is ONE supermassive black hole in the center of a blazar. “Standard model” = One supermassive black hole Seminar of the Astronomuical Institute

  9. However, there are quite a lot of suggestions that not ONE black hole but TWO are present in several blazars . . . Jet Secondary black hole Primary black hole Artist’s conception of a supermassive binary black hole (= BBH) system • Volonteri et al., 2003 • BBHs should be common • There is observational evidence for BBHs Accretion disk Seminar of the Astronomuical Institute

  10. Our blazar sample for grant proposal (Part I) • ON 231 • Possible periodicities: • 13.6 years in optical • (Liu et al., 1995) • 2. Mkn 421 • Possible periodicities: • 23 years in the optical band (Liu et al., 1997) • 104 second variations in the X-ray band (Marashi et al., 1999) • 3. 0109+224 • Possible periodicities: • Long-term oscillations of the base-level flux on a timescale of about 11.6 years (Smith & Nair, 1995) • 4. Mkn 501 • Possible periodicities: • 23 days in the X-ray and TeV band (Nishikawa et al., 1999) We have gathered following suggestions for periodicity in our blazar sample. Seminar of the Astronomuical Institute

  11. Our blazar sample for grant proposal (Part II) • 5. Mkn 766 • Possible periodicities: • 4200 seconds in the X-ray band (Boller et al., 2001) • 6. 3C 345 • Possible periodicities: • 5 and 11 years in the optical band (Caproni & Abraham, 2004) • 7. AO 0235+16 • Possible periodicities: • 5.7 years in the radio light curve (Raiteri et al., 2001) • 2.95 years in the optical light curve (Fan et al., 2002) • 8. 3C 279 • Possible periodicities: • 7.1 years in the long-term near infrared light curve (Fan, 1999) • 22-year period from movement of jet components(Abraham & Carrara, 1998) Seminar of the Astronomuical Institute

  12. Our blazar sample for grant proposal (Part III) The periodicity in the blazars may be a suggestion of binary black hole systems. • 9. PKS 0420-014 • Possible periodicities: • 13-months between • optical major outbursts • (Wagner et al., 1995) • 10. 0716+714 • Possible periodicities: • 0.7-year quasi-periodic ejection of VLBA components (Jorstad et al., 2001) • 12.5, 2.5 & 0.14-day periodicity of polarization in the optical band (Impey et al., 2000) • 4-day periodicity in the optical band (Heidt & Wagner, 1996) • 11. 3C 66a • Possible periodicities: • 2.5 years (Belokon & Babadzhanyants, 2003), 275 and 64 days in the optical band (Marchenko, 1999; Lainela et al., 1999) Seminar of the Astronomuical Institute

  13. Origin of Binary Black Holes (= BBHs) The origin of the binary black hole system is in the merging of galaxies. If each galaxy contains a supermassive black hole  a binary black hole system is formed (frequent in clusters) Hibbard & van Gorkom, 1996 Seminar of the Astronomuical Institute

  14. Observational evidence for BBH systems • NGC 6240 Hubble, optical Chandra, X-ray Komossa et al., 2003 • High-redshift quasars observed in pairs • Q1343.4+2640, LBQS0103-2753, UM425,... • Komossa, 2003 True pairs x Chance alignments x Lensing effect Seminar of the Astronomuical Institute

  15. The periods in our “grant proposal” sample of 11 blazars are not confirmed at all as their light curves are not well-sampled and do not involve much historical data. We apply the following steps in our work: • Gathering of optical data • Photographic plate collections • Sonneberg Observatory, Germany (280 000 plates) • Harvard College Observatory, USA (600 000 plates) • UKSTU plate collection ROE Edinburgh, UK (18 000 plates) • Observatory Leiden, NL (40 000 plates) • Papers • Observational campaigns archives • Gathering support data from other energy bands • Periodicity analysis of the optical light curve • An overall analysis to adopt a BBH model • Establishing statistical results based on our sample of 11 blazars Seminar of the Astronomuical Institute

  16. Possible origin of periods in blazars It is necessary to watch out for the whole spectrum behavior and for the behavior of colors and flares to be able to distinguish between different origin of periods in blazars. Seminar of the Astronomuical Institute

  17. Blazars & support data from other bands Blazar emit their energy from radio to TeV band. Data in all wavelength enable to specify the nature of blazars. Spectral energy distribution of blazars Seminar of the Astronomuical Institute

  18. Optical data gathering & Periodicity analysis Sextractor screenshot Sextractor processing Determination of magnitude of a specific object in individual plates Modified Argelander method Sonneberg photographic plate Thousands of photographic plates ANALYSIS OF THE TIME SERIES • Stellingwerf’s method (folded light curves) • Deeming method • CLEAN algorithm • Wavelets analysis Seminar of the Astronomuical Institute

  19. Violent optical variability of BL Lac on a long time time scale Seminar of the Astronomuical Institute

  20. There is wide range of possible interpretations of periods found in the light curves (in different bands). We present a short introduction into the interpretation of periods using the supermassive binary black hole scenario and the following designation: q angle between jet and observer M mass of the primary BH m mass of the secondary BH Torbitalorbital period rm separation of black holes G Lorenz factor of the jet b vjet/c bapparent apparent b z redshift Seminar of the Astronomuical Institute

  21. Periodicity interpretation – origin in jet I Periods originating in the jet can be drastically shortened due to relativistic effects and small viewing angles: Angle qbetween direction to observer and jet Tobservedisany observed period originating in jet Direction to the observer q Direction of the jet outflow Time: Dt.(1-v/c.cosq) Seminar of the Astronomuical Institute

  22. Periodicity interpretation – origin in jet II The Lorenz factor G can be estimated i.e. from superluminal motion. Apparent speeds higher than c are observed in the jet Time: Dt.(1-v/c.cosq) From optical or VLBI measurements The max. apparent speed can be used as an estimate of G. Typical values of G: 10-15 Seminar of the Astronomuical Institute

  23. Periodicity interpretation – origin in jet III The period observed in the jet may be induced i.e. by the tidal effect of the secondary black hole on the accretion disk of the primary. Figure credit: Romero, Fan & Nuza, 2003 Seminar of the Astronomuical Institute

  24. Periodicity interpretation – origin in jet IV • The periods originating in the jet period may be also caused by: • knots rotating in the jet • emission from jet carried by the secondary BH • components moving in helically distorted jets Seminar of the Astronomuical Institute

  25. Periodicity interpretation – origin in the accretion disk • While the secondary is piercing a channel into the accretion disk of the primary the gas gets heated and radiates. • Timing of the outbursts enables the determination of the orbital period. • Color behavior may support or reject the origin of the periodicity in disk!! The secondary BH crosses twice the disk The origin of the period in disk may be the case of blazar OJ 287: “Predicting the next outburst of OJ 287”, Valtonen, M.; Lehto, H. . . . Hudec, R.; Basta, M . . ., in preparation for ApJ Seminar of the Astronomuical Institute

  26. Determination of the mass of the primary via high energy data support Estimates of the mass of the primary black hole can be sometimes obtained using the high energy data. g-ray e+, e- X-ray Estimating d and measuring variability timescales in gamma-ray band gives an estimate of the mass of the primary black hole. Seminar of the Astronomuical Institute

  27. Determination of the mass of the secondary from periodicity studies Stages of evolution of a BBH system: Dynamical friction stage Non-hard binary stageHard-binary stage Gravitational radiation stage: The loss of energy via gravitational radiation results in the orbit decay Time: Dt.(1-v/c.cosq) Knowing Torbital ,M and errors in determination of Torbital, can lead to an estimate of the upper limit ofm. Seminar of the Astronomuical Institute

  28. Predicting the next outburst of OJ 287 Valtonen, M.; Lehto, H.; . . Hudec, R.; Basta, M; . . In preparation for ApJ We participate in a paper in preparation where a specific model was applied to the blazar OJ 287. OJ 287 light curve Scalegram for OJ 287 Seminar of the Astronomuical Institute

  29. Conclusion and future plans • It is highly possible that the engine of blazars and AGN is not associated with one supermassive black hole but with two supermassive black holes. • Periodicity studies supported by data from other energy bands and supported by spectral/color and flare behavior may help • to establish a viable model. • Our studies are based on gathering the data for a larger sample of blazars and carrying out the appropriate analysis, results discussion and establishing a new model of blazar. • We have applied our approach fully already to OJ 287. The processing of other blazars is in the stage of data gathering and period analysis. Seminar of the Astronomuical Institute

  30. References and acknowledgements Some fundamental papers Antonucci, R.: Unified models for active galactic nuclei and quasar, 1993, ARA&A, 31, 473A Bromm, V. & Loeb, A.: Formation of the first supermassive black holes, 2003, ApJ, 596, 34B Conway, J. E. & Murphy, D. W.: Helical jets and the misalignment distribution for core-dominated radio sources, 1993, ApJ, 411, 89C Conway, J. E. & Wrobel, J. M. A helical jet in the orthogonally misaligned BL Lacertae object Markarian 501, 1995, ApJ, 439, 98 De Paolis et al., F.: Binary black holes in Mkns as sources of gravitational radiation for space based interferometer, 2003, A&A, 410, 741 Faber, S. M. et al.: The centres of early-type galaxies with HST. IV. Central parameter relations, 1997, AJ, 114, 1771F Fan, MNRAS, 1999, 308, 1032 Hardee. P. E.; Cooper, M. A. & Clarke, D. A.: On jet response to a driving frequency and the jets in 3C 449, 1994, ApJ, 424, 126H Katz, J. I.: A precessing disk in OJ 287, 1997, ApJ, 478, 527 Komossa, S.: Observational evidence for supermassive black hole binaries, 2003, AIPC, 686, 161K Komossa, S. et al.: Discovery of a binary active galactic nucleus in the ultraluminous infrared galaxy NGC 6240 using Chandra, 2003, ApJ, 582, 15 Lehto, H. & Valtonen, M.: OJ 287 outburst structure and binary black hole model, 1996, ApJ, 460, 207 Liu et al., A&A, 1995, 295, 1 Magorrian, J. et al.: The demography of massive dark objects in galaxy centres, 1998, AJ, 115, 2285M Raiteri, C. M.: Optical and radio variability of the BL Lacertae object AO 0235+16: A possible 5-6 year periodicity, 2001, A&A, 377, 396R Rieger, F. M. & Mannheim, K.: Implications of a possible 23 day periodicity for binary black hole models in Mkn 501, 2000, A&A, 359, 948R Romero, G. E.; Fan, Jun-Hui & Nuza, S. E.: The binary black hole scenario for the BL Lacertae object AO 0235+16, 2003, ChJAA, 3, 513R Sillanpaa, et al.: OJ 287 – Binary pair of supermassive black holes, 1988, ApJ, 325, 628 Smith & Nair, 1995, PASP, 107, 863 Valtaoja, E. et al.: Radio Monitoring of OJ 287 and Binary Black Hole Models for Periodic Outbursts; 2000, ApJ, 531, 744 Villata, M. & Raiteri, C. M.: Helical jets in blazars. I. The case of MKN 501, 1999, A&A, 347, 30V Villata, M. et al.: A beaming model for the OJ 287 periodic optical outbursts, 1998, MNRAS, 293, L13 Volonteri, M. et al., The assembly and merging history of supermassive black holes in hierarchical models of galaxy formation, 2003, ApJ, 582, 559 Yu, Q.: Evolution of massive binary black holes, 2002, MNRAS, 331, 935Y Xu, W. et al.: The bimodal distribution of misalignment angle in powerful extragalactic radio sources, 1994, cers.conf, 7 Some web references and photo credits http://www.gsfc.nasa.gov http://chandra.harvard.edu http://users.rowan.edu/~polikar/WAVELETS/WTtutorial.html http://www-glast.stanford.edu/ Seminar of the Astronomuical Institute THANKS

  31. Last thought I expect to pass through this world but once; any good thing therefore that I can do, or any kindness that I can show to any fellow creatures, let me do it now; let me not defer or neglect it, for I shall not pass this way again. Ettiene De Grallet My thanks and acknowledgments for the support with my scientific research and this presentation are passed to the following: René Hudec,Aimo Sillanpaa,Harry Lehto,Mauri Valtonen, Adam Hill, Filip Munz, Martin Toast Topinka, Ivana Joanne Stoklasová, Libor “Měkká koza“ Švéda, Petr Skalický, Martin “Matesí Péro” Jelínek, Petr Sobotka Seminar of the Astronomuical Institute

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