Spectral Evolution in High Redshift Quasars from the Final BOSS Sample

Abstract

We report on the diversity in quasar spectra from the Baryon Oscillation Spectroscopic Survey. After filtering the spectra to mitigate selection effects and Malmquist bias associated with a nearly flux-limited sample, we create high signal-to-noise ratio composite spectra from 58,656 quasars (2.1 \le z \le 3.5), binned by luminosity, spectral index, and redshift. With these composite spectra, we confirm the traditional Baldwin effect (BE, i.e., the anticorrelation of C IV equivalent width (EW) and luminosity) that follows the relation W_λ\propto L^{β_w} with slope β_w = -0.35 \pm 0.004, -0.35 \pm 0.005, and -0.41 \pm 0.005 for z = 2.25, 2.46, and 2.84, respectively. In addition to the redshift evolution in the slope of the BE, we find redshift evolution in average quasar spectral features at fixed luminosity. The spectroscopic signature of the redshift evolution is correlated at 98% with the signature of varying luminosity, indicating that they arise from the same physical mechanism. At a fixed luminosity, the average C IV FWHM decreases with increasing redshift and is anti-correlated with C IV EW. The spectroscopic signature associated with C IV FWHM suggests that the trends in luminosity and redshift are likely caused by a superposition of effects that are related to black hole mass and Eddington ratio. The redshift evolution is the consequence of a changing balance between these two quantities as quasars evolve toward a population with lower typical accretion rates at a given black hole mass.

arXiv comment15 pages, 11 figures, to be published in ApJ

References in corpus (70)

• The Sloan Digital Sky Survey: Technical Summary
• Detection of the Baryon Acoustic Peak in the Large-Scale Correlation Function of SDSS Luminous Red Galaxies
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample
• The UKIRT Infrared Deep Sky Survey (UKIDSS)
• The Galaxy Evolution Explorer: A Space Ultraviolet Survey Mission
• The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III
• The 2.5 m Telescope of the Sloan Digital Sky Survey
• SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems
• The 2dF Galaxy Redshift Survey: Power-spectrum analysis of the final dataset and cosmological implications
• The Baryon Oscillation Spectroscopic Survey of SDSS-III
• Composite Quasar Spectra From the Sloan Digital Sky Survey
• The Multi-Object, Fiber-Fed Spectrographs for SDSS and the Baryon Oscillation Spectroscopic Survey
• Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Quasar Sample
• Baryon Acoustic Oscillations in the Lyα forest of BOSS DR11 quasars
• The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Overview and Early Data
• Spectral Classification and Redshift Measurement for the SDSS-III Baryon Oscillation Spectroscopic Survey
• The Rest-Frame Extreme Ultraviolet Spectral Properties of QSOs
• Black Hole Mass and Eddington Ratio as Drivers for the Observable Properties of Radio-Loud and Radio-Quiet QSOs
• A Composite HST Spectrum of Quasars
• Black Hole Masses and Eddington Ratios at 0.3<z<4
• Unification of Luminous Type 1 Quasars through CIV Emission
• The diversity of quasars unified by accretion and orientation
• The FIRST Bright Quasar Survey. II. 60 Nights and 1200 Spectra Later
• Efficient Photometric Selection of Quasars from the Sloan Digital Sky Survey: II. ~1,000,000 Quasars from Data Release Six
• Column density distribution and cosmological mass density of neutral gas: Sloan Digital Sky Survey-III Data Release 9
• The SDSS-III Baryon Oscillation Spectroscopic Survey: Quasar Target Selection for Data Release Nine
• The cosmic evolution of massive black holes in the Horizon-AGN simulation
• Spectral Classification of Quasars in the Sloan Digital Sky Survey: Eigenspectra; Redshift and Luminosity Effects
• Black Hole Growth to z = 2 - I: Improved Virial Methods for Measuring M_BH and L/L_Edd
• CIV 1549 as an Eigenvector 1 Parameter for Active Galactic Nuclei
• Think Outside the Color Box: Probabilistic Target Selection and the SDSS-XDQSO Quasar Targeting Catalog
• A Composite Extreme Ultraviolet QSO Spectrum from the Far Ultraviolet Spectroscopic Explorer
• Composite Spectra from the FIRST Bright Quasar Survey
• The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Quasar Target Selection
• The Sloan Digital Sky Survey Reverberation Mapping Project: Technical Overview
• Continuum and Emission Line Strength Relations for a large Active Galactic Nuclei Sample
• X-ray Insights into the Nature of PHL 1811 Analogs and Weak Emission-Line Quasars: Unification with a Geometrically Thick Accretion Disk?
• Black hole evolution: III. Statistical properties of mass growth and spin evolution using large-scale hydrodynamical cosmological simulations
• Black-Hole Mass and Growth Rate at High Redshift
• HST-COS Observations of AGN. I. Ultraviolet Composite Spectra of the Ionizing Continuum and Emission Lines
• An X-shooter composite of bright 1 < z < 2 quasars from UV to infrared
• Active galactic nuclei at z~1.5: II. Black Hole Mass estimation by means of broad emission lines
• XMM-Newton spectroscopy of high-redshift QSOs
• Conference Summary: AGN Physics with the Sloan Digital Sky Survey
• Photometric redshifts and quasar probabilities from a single, data-driven generative model
• Searching For the Physical Drivers of Eigenvector 1: Influence of Black Hole Mass and Eddington Ratio
• HST-COS Observations of AGN. II. Extended Survey of Ultraviolet Composite Spectra from 159 Active Galactic Nuclei
• A Principal Component Analysis of quasar UV spectra at z~3
• CIV Emission Line Properties and Systematic Trends in Quasar Black Hole Mass Estimates
• Average UV Quasar Spectra in the Context of Eigenvector 1: A Baldwin Effect Governed by Eddington Ratio?
• Active Galactic Nuclei Emission-Line Properties Versus Eddington Ratio
• The correlation of line strength with luminosity and redshift from composite QSO spectra
• A Population of X-ray Weak Quasars: PHL 1811 Analogs at High Redshift
• Quasars as Cosmological Probes: The Ionizing Continuum, Gas Metallicity and the EW-L Relation
• The Baldwin Effect and Black Hole Accretion: A Spectral Principal Component Analysis of a Complete QSO Sample
• Quasar Evolution and the Baldwin Effect in the Large Bright Quasar Survey
• A Simple Likelihood Method for Quasar Target Selection
• Photoionized HBeta Emission in NGC 5548: It Breathes!
• An Intrinsic Baldwin Effect in the H-beta Broad Emission Line in the Spectrum of NGC 5548
• The CIV Baldwin effect in QSOs from Seventh Data Release of the Sloan Digital Sky Survey
• The Composite Spectrum of BOSS Quasars Selected for Studies of the Lyman-alpha Forest
• Probing the Origins of the CIV and Fe Kalpha Baldwin Effect
• GTC Spectra of z ~ 2.3 Quasars: Comparison with Local Luminosity Analogues
• The Origin and Evolution of \civ Baldwin Effect in QSOs from the Sloan Digital Sky Survey
• HST-COS Observations of AGNs. III. Spectral Constraints in the Lyman Continuum from Composite COS/G140L Data
• The role of the Gamma-Eddington ratio relation on the X-ray Baldwin effect in Active Galactic Nuclei
• Observing Supermassive Black Holes across cosmic time: from phenomenology to physics
• Comparing Hbeta Line Profiles in the 4D Eigenvector 1 Context
• On the origins of C IV absorption profile diversity in broad absorption line quasars
• Composite spectra of quasars with different UV spectral index

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• The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
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• The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Large-scale Structure Catalogs for Cosmological Analysis
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• Modelling type 1 quasar colours in the era of Rubin and Euclid
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• High-redshift galaxies and black holes in the eyes of JWST: a population synthesis model from infrared to X-rays
• Testing AGN outflow and accretion models with CIV and HeII emission line demographics in z=2 quasars
• Primordial non-Gaussianity from the Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey I: Catalogue Preparation and Systematic Mitigation
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• The first high-redshift changing-look quasars
• Emission Line Properties of Seyfert Galaxies in the 12 Micron Sample
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• Systematic Redshift of the Fe III UV Lines in Quasars. Measuring Supermassive Black Hole Masses under the Gravitational Redshift Hypothesis
• A giant Ly$\alpha$ nebula and a small-scale clumpy outflow in the system of the exotic quasar J0952+0114 unveiled by MUSE
• Quasar Factor Analysis -- An Unsupervised and Probabilistic Quasar Continuum Prediction Algorithm with Latent Factor Analysis
• Measurements of effective optical depth in the Ly$\alpha$ forest from the BOSS DR12 Quasar sample
• Measuring Supermassive Black Hole Masses: Correlation between the Redshifts of the Fe III UV Lines and the Widths of Broad Emission Lines
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• Individual Estimates of the Virial Factor in 10 Quasars: Implications on the Kinematics of the Broad Line Region
• Testing Einstein's Equivalence Principle and its Cosmological Evolution from Quasar Gravitational Redshifts
• Ultraviolet Spectral Evidence for Ansky as a Slowly Evolving Featureless Tidal Disruption Event with Quasiperiodic Eruptions
• Modeling the Spectral Diversity of Quasars in the Sixteenth Data Release from the Sloan Digital Sky Survey
• When Spectral Modeling Meets Convolutional Networks: A Method for Discovering Reionization-era Lensed Quasars in Multi-band Imaging Data
• The Spectroscopic Signature of Variability in High-Redshift Quasars
• The miniJPAS survey quasar selection V: combined algorithm
• Back to basics: Little Red Dots as galaxies and dust-obscured AGNs in a synthetic NIRCam sky simulated with L-GalaxiesBH