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Local samples of quiescent galaxies with dynamically measured black hole masses (M bh ) may suffer from an angular resolution-related selection effect, which could bias the observed scaling relations between M bh and host galaxy properties away from the intrinsic relations. In particular, previous work has shown that the observed M bh -M star relation is more strongly biased than the M bh -σ relation. Local samples of active galactic nuclei (AGN) do not suffer from this selection effect, as in these samples M bh is estimated from megamasers and/or reverberation mapping-based techniques. With the exception of megamasers, M bh -estimates in these AGN samples are proportional to a virial coefficient f vir . Direct modelling of the broad line region suggests that f vir ∼ 3.5. However, this results in a M bh -M star relation for AGN which lies below and is steeper than the one observed for quiescent black hole samples. A similar though milder trend is seen for the M bh -σ relation. Matching the high-mass end of the M bh -M star and M bh -σ relations observed in quiescent samples requires f vir 15 and f vir 7, respectively. On the other hand, f vir ∼ 3.5 yields M bh -σ and M bh -M star relations for AGN which are remarkably consistent with the expected "intrinsic" correlations for quiescent samples (i.e., once account has been made of the angular resolution-related selection effect), providing additional evidence that the sample of local quiescent black holes is biased. We also show that, as is the case for quiescent black holes, the M bh -M star scaling relation of AGN is driven by σ, thus providing additional key constraints to black hole-galaxy co-evolution models.

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Abstract.Since the North Atla, ntic continenta,1 breakup in the early Tertiary, the process of rifting above a. mantle plume has produced large thicknesses of igneous crust. We report results of an integrated offshore-onshore seismic study of the crust and upper mantle along a transect of the aseismic Faroe-Iceland Ridge, between the continental fragment beneath the Faroe Islands and the present-day spreading center in northeast Iceland. Norma.l-incidence seismic data provide an image of the uppermost crust, which is complemented by a velocity model from streamer refra, ction a, nalyses.

We analyzed a large sample of radio-loud and radio-quiet quasar spectra at redshift 1.0 ≤ z ≤ 1.2 to compare the inferred underlying quasar continuum slopes (after removal of the host galaxy contribution) with accretion disk models. The latter predict redder (decreasing) α 3000 continuum slopes (L ν ∝ ν α at 3000Å) with increasing black hole mass, bluer α 3000 with increasing luminosity at 3000Å, and bluer α 3000 with increasing spin of the black hole, when all other parameters are held fixed. We find no clear evidence for any of these predictions in the data. In particular we find that: (i) α 3000 shows no significant dependence on black hole mass or luminosity. Dedicated Monte Carlo tests suggest that the substantial observational uncertainties in the black hole virial masses can effectively erase any intrinsic dependence of α 3000 on black hole mass, in line with some previous studies. (ii) The mean slope α 3000 of radio-loud sources, thought to be produced by rapidly spinning black holes, is comparable to, or even redder than, that of radio-quiet quasars. Indeed, although quasars appear to become more radio loud with decreasing luminosity, we still do not detect any significant dependence of α 3000 on radio loudness. The predicted mean α 3000 slopes tend to be bluer than in the data. Disk models with high inclinations and dust extinction tend to produce redder slopes closer to empirical estimates. Our mean α 3000 values are close to the ones independently inferred at z < 0.5 suggesting weak evolution with redshift, at least for moderately luminous quasars.