EVIDENCE FOR NON-EVOLVING Fe II/Mg II RATIOS IN RAPIDLY ACCRETING z ∼ 6 QSOs
TL;DR: In this article, the authors present the most extensive consistent analysis to date of 4 4 sample and the log (L bol/L Edd) = −0.80 (l bol/l Edd ~ 0.16) with a scatter of 0.24
Abstract: Quasars (QSOs) at the highest known redshift (z ~ 6) are unique probes of the early growth of supermassive black holes (BHs). Until now, only the most luminous QSOs have been studied, often one object at a time. Here we present the most extensive consistent analysis to date of 4 4 sample and the log (L bol/L Edd) = –0.80 (L bol/L Edd ~ 0.16) with a scatter of 0.24 dex for the 0.35 4 sources are accreting significantly faster than the lower-redshift ones. We show that the derived Fe II/Mg II ratios depend sensitively on the analysis performed: our self-consistent, homogeneous analysis significantly reduces the Fe II/Mg II scatter found in previous studies. The measured Fe II/Mg II line ratios show no sign of evolution with cosmic time in the redshift range 4 < z < 6.5. If the Fe II/Mg II line ratio is used as a secondary proxy of the Fe/Mg abundance ratio, this implies that the QSOs in our sample have undergone a major episode of Fe enrichment in the few 100 Myr preceding the cosmic age at which they are observed.
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01 Sep 1998
TL;DR: A stellar spectral flux library of wide spectral coverage and an example of its application are presented in this paper, which consists of 131 flux-calibrated spectra, encompassing all normal spectral types and luminosity classes at solar abundance, and metal-weak and metalrich F-K dwarf and G-K giant components.
Abstract: A stellar spectral flux library of wide spectral coverage and an example of its application are presented. The new library consists of 131 flux-calibrated spectra, encompassing all normal spectral types and luminosity classes at solar abundance, and metal-weak and metal-rich F-K dwarf and G-K giant components. Each library spectrum was formed by combining data from several sources overlapping in wavelength coverage. The SIMBAD database, measured colors, and line strengths were used to check that each input component has closely similar stellar type. The library has complete spectral coverage from 1150 to 10620 Afor all components and to 25000 Afor about half of them, mainly later types of solar abundance. Missing spectral coverage in the infrared currently consists of a smooth energy distribution formed from standard colors for the relevant types. The library is designed to permit inclusion of additional digital spectra, particularly of non-solar abundance stars in the infrared, as they become available. The library spectra are each given as Fl versus l, from 1150 to 25000 Ain steps of 5 A ˚. A program to combine the library spectra in the ratios appropriate to a selected isochrone is described and an example of a spectral component signature of a composite population of solar age and metallicity is illustrated. The library spectra and associated tables are available as text files by remote electronic access.
999 citations
TL;DR: The discovery of an ultraluminous quasar, SDSS J010013.02+280225.8, at redshift z = 6.30, which has an optical and near-infrared luminosity a few times greater than those of previously known z > 6 quasars.
Abstract: So far, roughly 40 quasars with redshifts greater than z = 6 have been discovered(1-8) Each quasar contains a black hole with a mass of about one billion solar masses (10(9) M-circle dot)(2,6,7,9-13) The existence of such black holes when the Universe was less than one billion years old presents substantial challenges to theories of the formation and growth of black holes and the coevolution of black holes and galaxies(14) Here we report the discovery of an ultraluminous quasar, SDSS J01001302+2802258, at redshift z = 630 It has an optical and near-infrared luminosity a few times greater than those of previously known z > 6 quasars On the basis of the deep absorption trough(15) on the blue side of the Lyman-alpha emission line in the spectrum, we estimate the proper size of the ionized proximity zone associated with the quasar to be about 26 million light years, larger than found with other z > 61 quasars with lower luminosities(16) We estimate (on the basis of a near-infrared spectrum) that the black hole has a mass of similar to 12 x 10(10) M-circle dot, which is consistent with the 13 x 10(10) M-circle dot derived by assuming an Eddington-limited accretion rate
764 citations
TL;DR: In this paper, the authors review the progress in addressing the key issues, motivated by the science presented at the What Drives the Growth of Black Holes? workshop held at Durham on 26 th ‐29 th July 2010, and discuss how these questions may be tackled with current and future facilities.
557 citations
TL;DR: In this paper, the authors study the properties of black holes and their host galaxies across cosmic time in the Illustris simulation and find that the black hole mass density for redshifts z = 0-5 and the black holes mass function at 0 predicted by Illustris are in very good agreement with the most recent observational constraints.
Abstract: We study the properties of black holes and their host galaxies across cosmic time in the Illustris simulation. Illustris is a large-scale cosmological hydrodynamical simulation which resolves a (106.5 Mpc)^3 volume with more than 12 billion resolution elements and includes state-of-the-art physical models relevant for galaxy formation. We find that the black hole mass density for redshifts z = 0–5 and the black hole mass function at z = 0 predicted by Illustris are in very good agreement with the most recent observational constraints. We show that the bolometric and hard X-ray luminosity functions of active galactic nuclei (AGN) at z = 0 and 1 reproduce observational data very well over the full dynamic range probed. Unless the bolometric corrections are largely underestimated, this requires radiative efficiencies to be on average low, ϵ_r ≲ 0.1, noting however that in our model radiative efficiencies are degenerate with black hole feedback efficiencies. Cosmic downsizing of the AGN population is in broad agreement with the findings from X-ray surveys, but we predict a larger number density of faint AGN at high redshifts than currently inferred. We also study black hole–host galaxy scaling relations as a function of galaxy morphology, colour and specific star formation rate. We find that black holes and galaxies co-evolve at the massive end, but for low mass, blue and star-forming galaxies there is no tight relation with either their central black hole masses or the nuclear AGN activity.
525 citations
Cites background from "EVIDENCE FOR NON-EVOLVING Fe II/Mg ..."
...Whereas for quasars at z ∼ 6−7 (Willott et al. 2010; De Rosa et al. 2011) the range ?...
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TL;DR: In this paper, the Atacama Large Millimeter/submillimeter Array (ALMA) observations of the [C Pi] 158 mu m fine structure line and dust continuum emission from the host galaxies of five redshift 6 quasars were carried out in the extended array at 0'' 7 resolution.
Abstract: We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the [C Pi] 158 mu m fine structure line and dust continuum emission from the host galaxies of five redshift 6 quasars. We also report complementary observations of 250 GHz dust continuum and CO (6-5) line emission from the z = 6.00 quasar SDSS J231038.88+185519.7 using the IRAM facilities. The ALMA observations were carried out in the extended array at 0.'' 7 resolution. We have detected the line and dust continuum in all five objects. The derived [C Pi] line luminosities are 1.6 x 10(9) to 8.7 x 10(9) L-circle dot and the [C Pi]-to-FIR luminosity ratios are 2.9-5.1 x 10(-4), which is comparable to the values found in other high-redshift quasar-starburst systems and local ultra-luminous infrared galaxies. The sources are marginally resolved and the intrinsic source sizes (major axis FWHM) are constrained to be 0.'' 3-0.'' 6 (i.e., 1.7-3.5 kpc) for the [C Pi] line emission and 0.'' 2-0.'' 4 (i.e., 1.2-2.3 kpc) for the continuum. These measurements indicate that there is vigorous star formation over the central few kpc in the quasar host galaxies. The ALMA observations also constrain the dynamical properties of the star-forming gas in the nuclear region. The intensity-weighted velocity maps of three sources show clear velocity gradients. Such velocity gradients are consistent with a rotating, gravitationally bound gas component, although they are not uniquely interpreted as such. Under the simplifying assumption of rotation, the implied dynamical masses within the [C Pi]-emitting regions are of order 10(10)-10(11) M-circle dot. Given these estimates, the mass ratios between the supermassive black holes and the spheroidal bulge are an order of magnitude higher than the mean value found in local spheroidal galaxies, which is in agreement with results from previous CO observations of high redshift quasars.
415 citations
Cites background from "EVIDENCE FOR NON-EVOLVING Fe II/Mg ..."
...…et al. 2009, 2011; and the Panoramic Survey Telescope and Rapid Response System [Pan-STARRS], Morganson et al. 2012) with optical z-band magnitudes from 18.8 to 24.4 and inferred SMBH masses from 108 to a few 109 M (Kurk et al. 2007; Jiang et al. 2007; Willott et al. 2010; De Rosa et al. 2011)....
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References
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TL;DR: The Sloan Digital Sky Survey (SDSS) as mentioned in this paper provides the data to support detailed investigations of the distribution of luminous and non-luminous matter in the Universe: a photometrically and astrometrically calibrated digital imaging survey of pi steradians above about Galactic latitude 30 degrees in five broad optical bands.
Abstract: The Sloan Digital Sky Survey (SDSS) will provide the data to support detailed investigations of the distribution of luminous and non- luminous matter in the Universe: a photometrically and astrometrically calibrated digital imaging survey of pi steradians above about Galactic latitude 30 degrees in five broad optical bands to a depth of g' about 23 magnitudes, and a spectroscopic survey of the approximately one million brightest galaxies and 10^5 brightest quasars found in the photometric object catalog produced by the imaging survey. This paper summarizes the observational parameters and data products of the SDSS, and serves as an introduction to extensive technical on-line documentation.
10,039 citations
Donald G. York1, Jennifer Adelman2, John E. Anderson2, Scott F. Anderson3 +148 more•Institutions (29)
TL;DR: The Sloan Digital Sky Survey (SDSS) as discussed by the authors provides the data to support detailed investigations of the distribution of luminous and non-luminous matter in the universe: a photometrically and astrometrically calibrated digital imaging survey of π sr above about Galactic latitude 30° in five broad optical bands to a depth of g' ~ 23 mag.
Abstract: The Sloan Digital Sky Survey (SDSS) will provide the data to support detailed investigations of the distribution of luminous and nonluminous matter in the universe: a photometrically and astrometrically calibrated digital imaging survey of π sr above about Galactic latitude 30° in five broad optical bands to a depth of g' ~ 23 mag, and a spectroscopic survey of the approximately 106 brightest galaxies and 105 brightest quasars found in the photometric object catalog produced by the imaging survey. This paper summarizes the observational parameters and data products of the SDSS and serves as an introduction to extensive technical on-line documentation.
9,835 citations
"EVIDENCE FOR NON-EVOLVING Fe II/Mg ..." refers background in this paper
...…have been discovered (Fan et al. 2000, 2001, 2003, 2004, 2006; Jiang et al. 2008, 2009; Willott et al. 2007, 2010) thanks to the Sloan Digital Sky Survey (SDSS, York et al. 2000) and other large multi-wavelength surveys such as the Canada France High-z Quasar Survey (CFHQS, Willott et al. 2007)....
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TL;DR: In this article, a simple cosmological model with only six parameters (matter density, Omega_m h^2, baryon density, BH 2, Hubble Constant, H_0, amplitude of fluctuations, sigma_8, optical depth, tau, and a slope for the scalar perturbation spectrum, n_s) was proposed to fit the three-year WMAP temperature and polarization data.
Abstract: A simple cosmological model with only six parameters (matter density, Omega_m h^2, baryon density, Omega_b h^2, Hubble Constant, H_0, amplitude of fluctuations, sigma_8, optical depth, tau, and a slope for the scalar perturbation spectrum, n_s) fits not only the three year WMAP temperature and polarization data, but also small scale CMB data, light element abundances, large-scale structure observations, and the supernova luminosity/distance relationship. Using WMAP data only, the best fit values for cosmological parameters for the power-law flat LCDM model are (Omega_m h^2, Omega_b h^2, h, n_s, tau, sigma_8) = 0.1277+0.0080-0.0079, 0.02229+-0.00073, 0.732+0.031-0.032, 0.958+-0.016, 0.089+-0.030, 0.761+0.049-0.048). The three year data dramatically shrink the allowed volume in this six dimensional parameter space. Assuming that the primordial fluctuations are adiabatic with a power law spectrum, the WMAP data_alone_ require dark matter, and favor a spectral index that is significantly less than the Harrison-Zel'dovich-Peebles scale-invariant spectrum (n_s=1, r=0). Models that suppress large-scale power through a running spectral index or a large-scale cut-off in the power spectrum are a better fit to the WMAP and small scale CMB data than the power-law LCDM model; however, the improvement in the fit to the WMAP data is only Delta chi^2 = 3 for 1 extra degree of freedom. The combination of WMAP and other astronomical data yields significant constraints on the geometry of the universe, the equation of state of the dark energy, the gravitational wave energy density, and neutrino properties. Consistent with the predictions of simple inflationary theories, we detect no significant deviations from Gaussianity in the CMB maps.
6,295 citations
TL;DR: In this article, a simple cosmological model with only six parameters (matter density, Omega_m h^2, baryon density, BH density, Hubble Constant, H_0, amplitude of fluctuations, sigma_8, optical depth, tau, and a slope for the scalar perturbation spectrum, n_s) was proposed to fit the three-year WMAP temperature and polarization data.
Abstract: A simple cosmological model with only six parameters (matter density, Omega_m h^2, baryon density, Omega_b h^2, Hubble Constant, H_0, amplitude of fluctuations, sigma_8, optical depth, tau, and a slope for the scalar perturbation spectrum, n_s) fits not only the three year WMAP temperature and polarization data, but also small scale CMB data, light element abundances, large-scale structure observations, and the supernova luminosity/distance relationship. Using WMAP data only, the best fit values for cosmological parameters for the power-law flat LCDM model are (Omega_m h^2, Omega_b h^2, h, n_s, tau, sigma_8) = 0.1277+0.0080-0.0079, 0.02229+-0.00073, 0.732+0.031-0.032, 0.958+-0.016, 0.089+-0.030, 0.761+0.049-0.048). The three year data dramatically shrink the allowed volume in this six dimensional parameter space. Assuming that the primordial fluctuations are adiabatic with a power law spectrum, the WMAP data_alone_ require dark matter, and favor a spectral index that is significantly less than the Harrison-Zel'dovich-Peebles scale-invariant spectrum (n_s=1, r=0). Models that suppress large-scale power through a running spectral index or a large-scale cut-off in the power spectrum are a better fit to the WMAP and small scale CMB data than the power-law LCDM model: however, the improvement in the fit to the WMAP data is only Delta chi^2 = 3 for 1 extra degree of freedom. The combination of WMAP and other astronomical data yields significant constraints on the geometry of the universe, the equation of state of the dark energy, the gravitational wave energy density, and neutrino properties. Consistent with the predictions of simple inflationary theories, we detect no significant deviations from Gaussianity in the CMB maps.
6,002 citations
TL;DR: In this article, the authors used spectro- photometrically monitored Palomar-Green quasars in order to obtain mea- surements of their emission lines and investigate the relationship between quasar luminosity, central black hole mass, and broad emission-line regions (BLRs) size in AGNs.
Abstract: Correlated variations in the line and continuum emission from active galactic nuclei (AGNs) can be used to determine the size and geometry of the broad emission-line regions (BLRs). We have spectro- photometrically monitored a well-de—ned sample of 28 Palomar-Green quasars in order to obtain mea- surements of their BLRs and to investigate the relationships between quasar luminosity, central black hole mass, and BLR size in AGNs. Spectrophotometry was obtained every 1¨4 months for 7.5 yr, yield- ing 20¨70 observing epochs per object. Both the continuum and emission-line —uxes of all of the quasars were observed to change during the duration of the observing program. Seventeen of the 28 objects were observed with adequate sampling independent observing epochs) to search for correlated variations (Z20 between the Balmer emission lines and the continuum —ux. For each of these 17 objects, a signi—cant correlation was observed, with the Balmer-line variations lagging those of the continuum by D100 days (rest frame). Our work increases the available luminosity range for studying the size-mass-luminosity relations in AGNs by 2 orders of magnitude and doubles the number of objects suitable for such studies. Combining our results with comparable published data available for Seyfert 1 galaxies, we —nd the BLR size scales with the rest-frame 5100 luminosity as L0.70B0.03. This determination of the scaling of the Ae size of the BLR as a function of luminosity is signi—cantly diUerent from those previously published and suggests that the eUective ionization parameter in AGNs may be a decreasing function of luminosity. We are also able to constrain, subject to our assumption that gravity dominates the motions of the BLR gas, the scaling relationship between the mass of the central black holes and the luminosity in AGNs. We —nd that the central mass scales with 5100 luminosity as M P L0.5B0.1. This is inconsistent with all Ae AGNs having optical luminosity that is a constant fraction of the Eddington luminosity. Subject headings: galaxies: activequasars: emission linesquasars: general
2,119 citations