AGN Unification in COSMOS Jonathan Trump Chris Impey
- Slides: 15
AGN Unification in COSMOS Jonathan Trump Chris Impey (Arizona), Martin Elvis, Brandon Kelly, Francesca Civano (Cf. A), Yoshi Taniguchi, Tohru Nagao (Ehime), Knud Jahnke, Marcella Brusa, Mara Salvato (Max -Planck), Pat Mc. Carthy (Carnegie), Anton Koekemoer (STSc. I)
COSMOS AGN survey • Four years of Magellan/IMACS & MMT/Hectospectroscopy over 2 deg 2 – 4 magnitudes fainter than SDSS – Type 1 AGN masses from virial scaling relations – Faint and obscured AGNs to z~1 • HST/ACS data for host morphologies to z~1 – Type 2 AGN masses from host-SMBH relations • Complete SEDs – Deep radio, IR, optical, UV, X-ray photometry – Bolometric luminosities • Bolometric luminosity + Mass = Accretion Rate
Accurate bolometric luminosities Model SED as accretion disk + X-ray corona Top: BL Bottom: NL (with host galaxy) Ignore extra reprocessed IR emission
Broad-Line AGN Masses • MBH ~ L 0. 5 × vfwhm 2, scatter of ~0. 4 dex • Calibrated from reverberation mapping of ~30 local AGN • Virial theorem: MBH ~ RBLRv. BLR 2 • RBLR~L 0. 5 (Kaspi et al. 2000, 07): scaling relations
Masses for Narrow-Line and Lineless AGNs • No broad emission lines. . . host – MBH relations instead • log(MBH/M⊙) ~ 0. 9 log(LK, bulge) − 31 • ~0. 35 dex scatter • Bulge luminosities from HST/ACS decompositions (Gabor+09) Graham 2007
AGN Fueling • LI/LEdd: accretion rate • With Ldisk/LX, Epeak of disk, X-ray slope
AGN Fueling Obscured Narrow-Line AGN Broad-Line AGN Unobscured Narrow-Line & Lineless AGN
AGN Fueling • Broad-line and Obscured Narrow-Line AGN limited by L/LEdd > 0. 01
AGN Fueling (unobscured only) • Disk gets brighter & hotter as accretion rate increases (at >3σ significance)
Accretion Rate and Radio Jets • Weakly accreting AGNs are more radio-loud! • Weak AGNs may be important for radio-mode feedback (e. g. heating cluster cores, IGM enrichment)
Accretion Rate and the IR “Torus” • Hot “torus” dust will have IR signature from 1 -10μm with αIR<0. 5 • Weak AGNs lack this IR signature • Can be explained by disk wind of both BLR & clumpy dust
AGN Fueling • With increasing accretion rate (LI/LEdd)… – Disk luminosity increases compared to X-rays – Disk becomes hotter – Weaker radio outflows – More likely to have IR “torus” signature – Broad emission lines appear (at LI/Ledd>0. 01) • Accretion rate is an “axis” of AGN unification – At low accretion rates, theory predicts a radiatively inefficient accretion flow (RIAF) which can produce these effects (Narayan & Mc. Clintock 2008)
Accretion in AGN Unification LI/LEdd > 0. 01 LI/LEdd < 0. 01
Reverberation Mapping • Measure time delay between variability in the broad lines and the continuum • Virial theorem: MBH ~ RBLRv. BLR 2 • RBLR=ctlag • v. BLR=v. FWHM • Calibrator for all nonlocal MBH!!!
Summary • Accretion Rate: new axis in AGN Unification – Low accretion rate: RIAF at inner radii – RIAF: radio-loud, cooler + weaker disk – BLR disappears at L/LEdd < 0. 01 – Torus weakens at low accretion rate? • Only possible with COSMOS!!! • Reverberation mapping for more accurate MBH in progress