1 / 20

Shuang-Nan Zhang ( 张双南 ), Yuan Liu ( 刘元 ), Jin Zhang ( 张晋 ) Institute of High Energy Physics

Dusty Torus Formation by Anisotropic Radiative Feedback of Active Galactic Nuclei: A Progress Report. Happy Birthday to Prof. Gerhard B ö rner!. Shuang-Nan Zhang ( 张双南 ), Yuan Liu ( 刘元 ), Jin Zhang ( 张晋 ) Institute of High Energy Physics National Astronomical Observatories of China

glain
Download Presentation

Shuang-Nan Zhang ( 张双南 ), Yuan Liu ( 刘元 ), Jin Zhang ( 张晋 ) Institute of High Energy Physics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Dusty Torus Formation by Anisotropic Radiative Feedback of Active Galactic Nuclei: A Progress Report Happy Birthday to Prof. Gerhard Börner! Shuang-Nan Zhang (张双南), Yuan Liu (刘元), Jin Zhang (张晋) Institute of High Energy Physics National Astronomical Observatories of China Chinese Academy of Sciences Liu,Y. & Zhang, S.N., 2011, ApJL, 728, L44

  2. The unified model of AGN Formation？ Dusty torus Evolution？

  3. AGN feedback The normal of the accretion disk • The distribution of the dust is anisotropic • The UV/optical radiation from the accretion disk is also anisotropic • The effect of radiation pressure is significant due to the presence of dust observer A~500

  4. The evolution of AGNs A B C Momentum effect of radiation

  5. Evaporation radius The inner radius of dust Energy effect of radiation

  6. The profile of a dusty torus

  7. NH-L/LEdd plane Raimundo, Fabian, Bauer et al. 2010

  8. The fraction of type 2 AGNs Hasinger 2008

  9. The inner radius of dust Suganuma et al. 2006

  10. The evolution of dusty torus Bright, with torus, but without bright BLR

  11. Weak line quasars Shemmer et al. 2009; EW<5 A; continuum similar to normal quasars

  12. Radio quiet BL Lac Plotkin et al. 2009 No obvious emission lines

  13. Polarization Test: Normal quasars 1-2% polarization comes from accretion disk emission! Kishimoto + 2008, Nature, 454, 492; Hu & Zhang in preparation

  14. Polarization Test: radio quiet Bl Lac • Very low polarization in continuum spectra: only two of 25 candidates are observed with weak polarization (Heidt & Nilsson 2011) • The continuum spectrum is consistent with disk origin

  15. Variability Test • Observations are quite limited • Weaker than radio loud BL Lac？ • Need more observations Plotkin et al. 2010

  16. Variability Test • SDSS Stripe 82（12 radio quiet BL Lac，4 WLQ，27 radio loud BL Lac） Radio quiet Radio loud

  17. Lightcurve amplitudes Radio loud Radio quiet

  18. Very weak short timescale variability with Lijiang 2.4 m at R-band SDSS 081250.80+522530.8 SDSS 090107.64+384658.8

  19. Dust Test in weak line quasars Black body from hot dust Diamond-Stanic et al. 2009 Evidence of hot dust in WLQ

  20. Conclusions • The distribution of dusty gas should also be anisotropic due to the influence of the anisotropic disk radiation. • This model can explain the presence of some obscured AGNs with high Eddington ratios and can also reproduce the observed decreasing fractionof type 2 AGNs with increasing luminosity. • Our model predicts the existence of bright AGNswith dusty tori, but without bright broad line regions. • Weak line quasars and radio quiet BL Lac? • Dust feature, weak polarization and variability confirm our prediction. Liu,Y. & Zhang, S.N., 2011, ApJL, 728, L44

More Related