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Image: C. Claver & N. Sharp (NOAO)

Image: C. Claver & N. Sharp (NOAO). Double-Peaked Balmer Line Emission in Active Galactic Nuclei Iskra Strateva, MPE. Chen & Halpern 1989.

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Image: C. Claver & N. Sharp (NOAO)

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  1. Image: C. Claver & N. Sharp (NOAO) Double-Peaked Balmer Line Emission in Active Galactic Nuclei Iskra Strateva, MPE Chen & Halpern 1989 N.Brandt M.Eracleous J.Gunn P.Hall L.Hao Ž.Ivezić G.Knap S.Komossa K.Lewis Li-Xin Li R.Lupton B.Paczynski G.Richards D.Schlegel M.Strauss W.Voges N.Zakamska October 2006 The Central Engine of AGN, Xi’an, China

  2. Outline • Optical/UV properties of double-peaked emitters (Eracleous+’94,’03, Strateva+’03, Wu & Liu’04) • What can we learn about the accretion disk from Balmer line profile fits (Strateva+’07, in prep.) • SWIFT/Chandra X-ray survey of FWHM>15000 km/s double-peaked emitters (Strateva+ ’07, in prep.) October 2006 The Central Engine of AGN, Xi’an, China

  3. Halpern+’96 Optical Properties of Double-Peaked Emitters How common are they? • 2-3% of z < 0.33 SDSS AGN (Strateva+03) • Up to 20% of Broad Line Radio Galaxies (Eracleous+’94, ’03) • Most FWHM >15000 km/s AGN Optical/UV properties: • Similar optical/UV luminosity • 10-5 < L/LEdd < 0.1 (Lewis+’06) • Broader low-ionization (Ha, Hb, MgII) lines • Single-peaked high-ionization (CIII], CIV, Lya) lines (Halpern+’96, Eracleous+’04) • Lower-ionizaion NLR (e.g. higher [OI]6300/[OIII]5007 ratios ) October 2006 The Central Engine of AGN, Xi’an, China

  4. Using Double-Peaked Emitters to Study the Accretion Disk disk inclinations: 20° < i < 60° inner and outer radii: 200RG< x1 < 1000RG 1000RG< x2 < 4000RG • Evidence for coplanar obscuring material • Outer radii consistent with onset of disk self gravity

  5. X-ray Spectra of Double-Peaked Emitters • 16 broadest double-peaked emitters with SWIFT and Chandra • 10 RL double-peaked emitters from the Eracleous et al. sample • 7 objects with serendipitous XMM/Chandra coverage Strateva+’06 • 22 objects with serendipitous ROSAT coverage October 2006 The Central Engine of AGN, Xi’an, China

  6. External Illumination of the Accretion Disk Is viscous dissipation of energy locally in the accretion disk sufficient to power lines of the observed strength? No!Based on 58 double-peaked emitters publishedby Eracleous+03, Strateva+06,and the newChandra/SWIFT sample. Eracleous+’03; Strateva+’06 October 2006 The Central Engine of AGN, Xi’an, China

  7. X-Ray Properties of Double-Peaked Emitters: II • Steeper aox at comparable 2500Å luminosity (Strateva+’06, Strateva+’07, in prep.) See also Wu & Liu’04 October 2006 The Central Engine of AGN, Xi’an, China

  8. Summary • 2-3% of optically selected AGN have double-peaked emission lines consistent with origin in the accretion disk; fully 1/5th of BLRGs and most FWHM>15000km/s AGN do • External illumination is necessary to produce lines of the observed strength • Not alwayslow accretion-rate, low-luminosity AGN • Accretion disk emission from few x100RG and outer radii consistent with the onset of gravitational instability (2000-4000RG); flatter disk emissivity profiles than simple point source; evidence for coplanar obscuring material • Double-peaked emitters are on average X-ray brighter than similar UV luminosity AGN • Intrinsic X-ray obscuration of 5x1020-1022 cm-2 in 8 of the 16 sources October 2006 The Central Engine of AGN, Xi’an, China

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