THE RADIUS-LUMINOSITY RELATIONSHIP FOR ACTIVE GALACTIC NUCLEI: THE EFFECT OF HOST-GALAXY STARLIGHT ON LUMINOSITY MEASUREMENTS. II. THE FULL SAMPLE OF REVERBERATION-MAPPED AGNs

Bentz, Misty C.; Peterson, B. M.; Netzer, H.; Pogge, Richard W.; Vestergaard, M.

doi:10.1088/0004-637x/697/1/160

Cited by 589 publications

(874 citation statements)

References 70 publications

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“…Quasars are another tool for reaching high redshifts, drawing on empirical correlations between line equivalent widths and luminosity (Baldwin, 1977) or between luminosity and the broad line region radius R BLR (Bentz et al, 2009). For example, Watson et al (2011) have recently proposed reverberation mapping (which measures R BLR ) of large quasar samples to constrain dark energy models.…”

Section: Alternative Distance Indicatorsmentioning

confidence: 99%

Observational probes of cosmic acceleration

et al. 2013

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The accelerating expansion of the universe is the most surprising cosmological discovery in many decades, implying that the universe is dominated by some form of "dark energy" with exotic physical properties, or that Einstein's theory of gravity breaks down on cosmological scales. The profound implications of cosmic acceleration have inspired ambitious efforts to understand its origin, with experiments that aim to measure the history of expansion and growth of structure with percent-level precision or higher. We review in detail the four most well established methods for making such measurements: Type Ia supernovae, baryon acoustic oscillations (BAO), weak gravitational lensing, and the abundance of galaxy clusters. We pay particular attention to the systematic uncertainties in these techniques and to strategies for controlling them at the level needed to exploit "Stage IV" dark energy facilities such as BigBOSS, LSST, Euclid, and WFIRST. We briefly review a number of other approaches including redshift-space distortions, the Alcock-Paczynski effect, and direct measurements of the Hubble constant H 0 . We present extensive forecasts for constraints on the dark energy equation of state and parameterized deviations from General Relativity, achievable with Stage III and Stage IV experimental programs that incorporate supernovae, BAO, weak lensing, and cosmic microwave background data. We also show the level of precision required for clusters or other methods to provide constraints competitive with those of these fiducial programs. We emphasize the value of a balanced program that employs several of the most powerful methods in combination, both to cross-check systematic uncertainties and to take advantage of complementary information. Surveys to probe cosmic acceleration produce data sets that support a wide range of scientific investigations, and they continue the longstanding astronomical tradition of mapping the universe in ever greater detail over ever larger scales.

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Section: Alternative Distance Indicatorsmentioning

confidence: 99%

Observational probes of cosmic acceleration

et al. 2013

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“…While the latter can be directly measured via reverberation mapping (e.g. Blandford & McKee 1982;Peterson et al 2004), for single epoch spectra, commonly the thereby-established scaling relation to the continuum luminosity (Kaspi et al 2000;Bentz et al 2009Bentz et al , 2013 is used. We (re-)computed BH masses consistently for all three samples using the formula from Shen et al (2011):…”

Section: Black Hole Massesmentioning

confidence: 99%

The cosmic growth of the active black hole population at 1 <z <2 in zCOSMOS, VVDS and SDSS

Schulze

Bongiorno

Gavignaud

et al. 2015

Monthly Notices of the Royal Astronomical Society

159

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We present a census of the active black hole population at 1 < z < 2, by constructing the bivariate distribution function of black hole mass and Eddington ratio, employing a maximum likelihood fitting technique. The study of the active black hole mass function (BHMF) and the Eddington ratio distribution function (ERDF) allows us to clearly disentangle the active galactic nuclei (AGN) downsizing phenomenon, present in the AGN luminosity function, into its physical processes of black hole mass downsizing and accretion rate evolution. We are utilizing type-1 AGN samples from three optical surveys (VVDS, zCOSMOS and SDSS), that cover a wide range of 3 dex in luminosity over our redshift interval of interest. We investigate the cosmic evolution of the AGN population as a function of AGN luminosity, black hole mass and accretion rate. Compared to z = 0, we find a distinct change in the shape of the BHMF and the ERDF, consistent with downsizing in black hole mass. The active fraction or duty cycle of type-1 AGN at z ∼ 1.5 is almost flat as a function of black hole mass, while it shows a strong decrease with increasing mass at z = 0. We are witnessing a phase of intense black hole growth, which is largely driven by the onset of AGN activity in massive black holes towards z = 2. We finally compare our results to numerical simulations and semi-empirical models and while we find reasonable agreement over certain parameter ranges, we highlight the need to refine these models in order to match our observations.

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“…There exists an empirical relation between the BLR size and the continuum luminosity in AGN/QSOs (e.g. Kaspi et al 2005;Bentz et al 2009). For the BAL region outside of BLR region, larger luminosity would lead to larger size, smaller orbital velocity of the BAL regions.…”

Section: Introductionmentioning

confidence: 99%

Variability of QSOs with variable regions in broad absorption troughs from the Sloan Digital Sky Survey

He¹,

Bian²,

Ge³

et al. 2015

Mon. Not. R. Astron. Soc.

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The variability of broad absorption lines is investigated for a sample of 188 broad-absorptionline (BAL) quasars (QSOs) (z > 1.7) with at least two-epoch observations from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), covering a time-scale of about 0.001 -3 years in the rest frame. Considering only the longest time-scale between epochs for each QSO, 73 variable regions in the C IV BAL troughs are detected for 43 BAL QSOs. The proportion of BAL QSOs showing variable regions increases with longer time-interval than about 1 year in the rest frame. The velocity width of variable regions is narrow compared to the BALtrough outflow velocity. For 43 BAL QSOs with variable regions, it is found that there is a medium strong correlation between the variation of the continuum luminosity at 1500 Å and the variation of the spectral index. With respect to the total 188 QSOs, larger proportion of BAL QSOs with variable regions appears bluer during their brighter phases, which implies that the origin of BAL variable regions is related to the central accretion process. For 43 BAL QSOs with variable regions, it is possible that there is a negative medium strong correlation between the absolute variation of the equivalent width and the Mg II -based black hole mass, and a medium strong correlation between the maximum outflow velocity of variable regions and the Eddington ratio. These results imply the connection between the BAL-trough variation and the central accretion process.

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THE RADIUS-LUMINOSITY RELATIONSHIP FOR ACTIVE GALACTIC NUCLEI: THE EFFECT OF HOST-GALAXY STARLIGHT ON LUMINOSITY MEASUREMENTS. II. THE FULL SAMPLE OF REVERBERATION-MAPPED AGNs

Cited by 589 publications

References 70 publications

Observational probes of cosmic acceleration

Observational probes of cosmic acceleration

The cosmic growth of the active black hole population at 1 <z <2 in zCOSMOS, VVDS and SDSS

Variability of QSOs with variable regions in broad absorption troughs from the Sloan Digital Sky Survey

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