Luminosity Indicators in the Spectra of Quasi-Stellar Objects

Baldwin, J. A.

doi:10.1086/155294

Cited by 553 publications

(467 citation statements)

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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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“…Three AGN samples have been used in this work: (1) the Large Bright Quasar Survey (LBQS) sample and references therein), (2) a sample of 104 high-redshift, highluminosity quasars with ground-based spectrophotometry Baldwin, Wampler, &Gaskell (1987), andBaldwin (1977). Forster et al (2001) supplied monochromatic luminosities and FWHMs for many emission lines in about 1000 LBQS quasars.…”

Section: The Samplementioning

confidence: 99%

The Largest Black Holes and the Most Luminous Galaxies

Netzer

2003

The Astrophysical Journal

125

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The empirical relationship between the broad-line region size and the source luminosity in active galactic nuclei (AGNs) is used to obtain black hole (BH) masses for a large number of quasars in three samples. The largest black hole masses exceed and are found to occur in the objects with the highest luminosities. 1010 M , Such BH masses, when converted to galaxy bulge mass and luminosity, indicate masses in excess of 13 10 M , and in excess of 700 km s Ϫ1 . Such massive galaxies have never been observed. The largest BHs reside, almost j * exclusively, in high-redshift quasars. All this is inconsistent with several suggested scenarios of BH and galaxy formation. Possible ways out are that either the observed size-luminosity relationship in low-luminosity AGNs does not extend to very high luminosity or else the correlations observed in the local universe do M -M -j BH bulge * not reflect the relation between those quantities at the epoch of galaxy formation.

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“…Croom et al (2002) analyzed the spectra of ∼ 22, 000 AGNs from the 2dF quasar redshift survey (2QZ) and claimed to see a decrease in the equivalent width (EW) of several narrow lines ([OII]λ3727, [NeV ]λ3426 and [N eIII]λ3870) with source luminosity. They suggested that at least part of this "Baldwin effect" (Baldwin 1977) is due to the increase in NLR size with source luminosity which leads to galactic-scale dimensions in the most luminous objects. Such NLRs are likely to escape the system leading to AGNs with weak or no NLR emission.…”

Section: Scaling and Weighing The Nlrmentioning

confidence: 99%

NLRs, BLRs and Starbursts at high redshift

Netzer

2004

Proc. IAU

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Abstract. New infrared spectroscopy of 22 high-luminosity high-redshift AGNs helps to test several suggestions regarding the mass, composition and size of the emission line regions in active galacic nuclei (AGN). A plot of the metalicity luminosity correlation over more than five orders of magnitude in luminosity shows that most narrow line Seyfert 1 galaxies fall outside of the general trend. However, when L/L Edd is plotted instead of luminosity, all sources follow the same trend suggesting this to be the primary driver of the correlation. Regarding the narrow emission lines in the most luminous sources, there is a dichotomy in the observed properties where 2/3 of the sources show very strong [O iii] λ5007 lines while the remaining 1/3 have no detectable NLR. On the basis of this I argue that earlier proposed relations of the typemust break down for RNLR exceeding a few kpc. Thus, NLRs in high luminosity AGN may be very different from those observed in nearby sources. In particular, some high luminosity sources may be in a phase of violent star-formation that produce a large quantity of high density gas in their central kpc.

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Luminosity Indicators in the Spectra of Quasi-Stellar Objects

Cited by 553 publications

References 0 publications

Observational probes of cosmic acceleration

Observational probes of cosmic acceleration

The Largest Black Holes and the Most Luminous Galaxies

NLRs, BLRs and Starbursts at high redshift

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