Diagnostics for the structure of AGNs’ broad line regions with reverberation mapping data: confirmation of the two-component broad line region model

Zhu, Ling; Zhang, Shuang‐Nan

doi:10.1007/s11433-010-0057-6

Cited by 5 publications

(4 citation statements)

References 11 publications

(20 reference statements)

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“…While NGC 5548 has the most extensive RM of all the AGN (Bentz et al 2007), frustratingly, it also has an irregular emission‐line profile. As noted by Zhu & Zhang (2010) and Zhu, Zhang & Tang (2009; see also Wandel et al 1999), the determination of the line width is problematic for these last two galaxies. To err on the side of caution, we present our analysis both with and without NGC 5548, finding consistent results.…”

Section: An Updated Galaxy Data Set and The Mbh−σ Diagram/relationmentioning

confidence: 94%

An expanded Mbh-σ diagram, and a new calibration of active galactic nuclei masses

Graham

Onken

Athanassoula

et al. 2011

Monthly Notices of the Royal Astronomical Society

428

549

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We present an updated and improved M bh -σ diagram containing 64 galaxies for which M bh measurements (not just upper limits) are available. Because of new and increased black hole masses at the high-mass end, and a better representation of barred galaxies at the low-mass end, the 'classical' (all morphological type) M bh -σ relation for predicting black hole masses is log (M bh /M ) = (8.13 ± 0.05) + (5.13 ± 0.34)log [σ /200 km s −1 ], with an rms scatter of 0.43 dex. Modifying the regression analysis to correct for a hitherto overlooked sample bias in which black holes with masses <10 6 M are not (yet) detectable, the relation steepens further to give log (M bh /M ) = (8.15 ± 0.06) + (5.95 ± 0.44)log [σ /200 km s −1 ]. We have also updated the 'barless' and 'elliptical-only' M bh -σ relations introduced by Graham and Hu in 2008 due to the offset nature of barred galaxies. These relations have a total scatter as low as 0.34 dex and currently define the upper envelope of points in the M bh -σ diagram. They also have a slope consistent with a value 5, in agreement with the prediction by Silk & Rees based on feedback from massive black holes in bulges built by monolithic collapse.Using updated virial products and velocity dispersions from 28 active galactic nuclei, we determine that the optimal scaling factor f -which brings their virial products in line with the 64 directly measured black hole masses -is 2.8 +0.7 −0.5 . This is roughly half the value reported by Onken et al. and Woo et al., and consequently halves the mass estimates of most high-redshift quasars. Given that barred galaxies are, on average, located ∼0.5 dex below the 'barless' and 'elliptical-only' M bh -σ relations, we have explored the results after separating the samples into barred and non-barred galaxies, and we have also developed a preliminary corrective term to the velocity dispersion based on bar dynamics. In addition, given the recently recognized coexistence of massive black holes and nuclear star clusters, we present the first ever (M bh + M nc )-σ diagram and begin to explore how galaxies shift from their former location in the M bh -σ diagram.

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Section: An Updated Galaxy Data Set and The Mbh−σ Diagram/relationmentioning

confidence: 94%

An expanded Mbh-σ diagram, and a new calibration of active galactic nuclei masses

Graham

Onken

Athanassoula

et al. 2011

Monthly Notices of the Royal Astronomical Society

428

549

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“…Even in these complex cases it appears that using a simplistic FWHM for the full Hβ profile (after subtraction of only the NLR emission) does not appreciably change the scaling relations used to estimate the black hole mass (Denney et al 2010). On the other hand, there is some evidence that only a few local Seyferts (2 of 10 studied) show a true ILR component; for these, the inclusion of the ILR component in the FWHM measurement leads to erroneous black hole estimations (Zhu et al 2009;Zhu & Zhang 2010). …”

Section: Introductionmentioning

confidence: 99%

Sub-millimeter detectedz ~ 2 radio-quiet QSOs

Orellana

Nagar

et al. 2011

A&A

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Context. We present near-IR spectroscopy of a sample of luminous (M B − 27.5; L bol > 10 14 L ), sub-millimeter-detected, dusty (M d ∼ 10 9 M ), radio-quiet quasi-stellar objects (QSOs) at z ∼ 2. Aims. A primary aim is to provide a more accurate QSO redshift determination in order to trace kinematics and inflows/outflows in these sub-mm bright QSOs. Additionally, the Hα and continuum properties allow an estimation of the black hole mass and accretion rate, offering insights into the starburst-AGN connection in sub-mm bright QSOs. Methods. We measure the redshift, width, and luminosity of the Hα line, and the continuum luminosity near Hα. Relative velocity differences between Hα and rest-frame UV emission lines are used to study the presence and strength of outflows/inflows. Luminosities and line widths are used to estimate the black hole masses, bolometric luminosities, Eddington fractions, and accretion rates; these are compared to the star-formation-rate (SFR), estimated from the sub-mm derived far-infrared (FIR) luminosity. Finally our sub-mmbright QSO sample is compared with other QSO samples at similar redshifts. Results. The Hα emission line was strongly detected in all sources. Two components -a very broad ( > ∼ 5000 km s −1 ) Gaussian and an intermediate-width ( > ∼ 1500 km s −1 ) Gaussian, were required to fit the Hα profile of all observed QSOs. Narrow ( < ∼ 1000 km s −1 ) lines were not detected in the sample QSOs. The rest-frame UV emission lines in these sub-mm bright QSOs show larger than average blue-shifted velocities, potentially tracing strong -up to 3000 km s −1 -outflows in the broad line region. With the exception of the one QSO which shows exceptionally broad Hα lines, the black hole masses of the QSO sample are in the range log M BH = 9.0−9.7 and the Eddington fractions are between 0.5 and ∼1. In black hole mass and accretion rate, this sub-mm bright QSO sample is indistinguishable from the Shemmer et al. (2004, ApJ, 614, 547) optically-bright QSO sample at z ∼ 2; the latter is likely dominated by sub-mm dim QSOs. Previous authors have demonstrated a correlation, over six orders of magnitude, between SFR and accretion rate in active galaxies: the sub-mm bright QSOs lie at the upper extremes of both quantities and their SFR is an order of magnitude higher than that predicted from the correlation.

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“…To end this review, we also refer the reader to recent papers in astrophysics [33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49]. Contained therein are applications to cosmology, for instance, work on the gamma-ray bursts.…”

Section: Discussionmentioning

confidence: 99%

Some recent progress in study of gravity and cosmology

2012

Chin. Sci. Bull.

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Diagnostics for the structure of AGNs’ broad line regions with reverberation mapping data: confirmation of the two-component broad line region model

Cited by 5 publications

References 11 publications

An expanded Mbh-σ diagram, and a new calibration of active galactic nuclei masses

An expanded Mbh-σ diagram, and a new calibration of active galactic nuclei masses

Sub-millimeter detectedz ~ 2 radio-quiet QSOs

Some recent progress in study of gravity and cosmology

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