Anisotropic quenching is detected at the highest redshift yet and linked to preprocessing dominating over intrahalo effects by ~20% along the major axis in a delay-then-rapid quenching model informed by cluster accretion histories.
Composite Quasar Spectra From the Sloan Digital Sky Survey
9 Pith papers cite this work. Polarity classification is still indexing.
9
Pith papers citing it
abstract
We have created a variety of composite quasar spectra using a homogeneous data set of over 2200 spectra from the Sloan Digital Sky Survey (SDSS). The quasar sample spans a redshift range of 0.044 <= z <= 4.789, and an absolute r' magnitude range of -18.0 to -26.5. The median composite covers a rest wavelength range from 800 - 8555A, and reaches a peak signal-to-noise ratio of over 300 per 1A resolution element in the rest frame. We have identified over 80 emission line features in the spectrum. Emission line peak velocity shifts of the broad permitted and semi-forbidden lines are strongly correlated with ionization energy, as previously suggested, but we find that the narrow forbidden lines are also shifted by amounts which are strongly correlated with ionization energy. The magnitude of the forbidden line shifts is < 100 km/s, compared to shifts of up to 550 km/s for some of the permitted and semi-forbidden lines. At wavelengths longer than the Ly-a emission, the continuum of the geometric mean composite is well-fit by two power-laws, with a break at approximately 5000A. The frequency power law index, alpha_nu, is -0.44 from 1300 - 5000A, and -2.45 redward of about 5000A. The abrupt change in slope can be accounted for partly by host galaxy contamination at low redshift. Stellar absorption lines, including higher-order Balmer lines, seen in the composites suggest that young or intermediate age stars make a significant contribution to the light of the host galaxies. An electronic table of the median quasar template is available.
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UNVERDICTED 9representative citing papers
Six z~2-3 quasars with extreme LoBAL outflows and weak UV lines are interpreted as weak-emission-line quasars emerging from dust cocoons via disc winds that shatter grains and produce steeper extinction.
Using simultaneous modeling of continuum lag-spectrum and broadband SED of Fairall 9 with the H0RIZON-AGN model, the authors obtain H0 = 72.4_{-3.7}^{+3.4} km s^{-1} Mpc^{-1}.
Requiring thermal stability and single-valuedness in the thin-disk Ṁ-Σ plane produces a viscosity law α(X) with X = P_gas/P_rad that eliminates the radiation-pressure dominated instability while preserving the effective-temperature profile.
Analysis of JWST/NIRSpec Prism spectra for 25 z>=10 galaxies finds burstiness correlates with strong UV lines, short depletion times, and DLA-induced redshift biases of 0.39 and 0.14 with marginal impact on UV luminosity density.
JWST data on LRDs and LBDs show AGN-like excitation, strong Lyα with broad components, and X-ray weakness, implying clumpy or equatorial geometries around growing black holes rather than complete gas envelopes.
Bayesian continuum fitting of 66 LRDs shows the BH* model fits ~6% best, rising to ~40% under AGN-disfavoring priors, with most objects stellar/AGN-dominated and possible evolutionary trends.
Variable column density and covering factor of three ionized absorbers in clumpy disk winds explain the X-ray variability in I Zw 1 with stable corona.
Shape-preserving LADE models with fixed local LF shape provide the statistically preferred description of UV QLF evolution to z~7.5 over flexible alternatives based on AIC/BIC.
citing papers explorer
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Anisotropic quenching beyond $z=1$ and its implications for preprocessing around high-redshift galaxy clusters
Anisotropic quenching is detected at the highest redshift yet and linked to preprocessing dominating over intrahalo effects by ~20% along the major axis in a delay-then-rapid quenching model informed by cluster accretion histories.
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Extreme outflow velocities and weak UV emission lines indicate quasars shedding their dust cocoons
Six z~2-3 quasars with extreme LoBAL outflows and weak UV lines are interpreted as weak-emission-line quasars emerging from dust cocoons via disc winds that shatter grains and produce steeper extinction.
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HALO II: Constraining Hubble constant $H_{0}$ through continuum delay fitting of Fairall 9
Using simultaneous modeling of continuum lag-spectrum and broadband SED of Fairall 9 with the H0RIZON-AGN model, the authors obtain H0 = 72.4_{-3.7}^{+3.4} km s^{-1} Mpc^{-1}.
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Radiation-pressure instability is an artifact of constant-$\alpha$ closure
Requiring thermal stability and single-valuedness in the thin-disk Ṁ-Σ plane produces a viscosity law α(X) with X = P_gas/P_rad that eliminates the radiation-pressure dominated instability while preserving the effective-temperature profile.
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JWST spectroscopy of galaxies at $z>10$: Damped Ly$\alpha$ absorbers reveal efficient star formation and hidden redshift biases
Analysis of JWST/NIRSpec Prism spectra for 25 z>=10 galaxies finds burstiness correlates with strong UV lines, short depletion times, and DLA-induced redshift biases of 0.39 and 0.14 with marginal impact on UV luminosity density.
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Little Red and Blue Dots: AGN-excited narrow lines, Lyman-$\alpha$ emission, and resemblance to standard quasars
JWST data on LRDs and LBDs show AGN-like excitation, strong Lyα with broad components, and X-ray weakness, implying clumpy or equatorial geometries around growing black holes rather than complete gas envelopes.
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Between Degeneracy and Evolution: UV-to-optical Insights into the BH$^*$ Model in Little Red Dots
Bayesian continuum fitting of 66 LRDs shows the BH* model fits ~6% best, rising to ~40% under AGN-disfavoring priors, with most objects stellar/AGN-dominated and possible evolutionary trends.
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Strong X-ray Variability of I Zwicky 1: Obscuration from Clumpy Accretion-Disk Winds
Variable column density and covering factor of three ionized absorbers in clumpy disk winds explain the X-ray variability in I Zw 1 with stable corona.
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Shape-Preserving Evolution of the Global Ultraviolet Quasar Luminosity Function to $z\simeq7.5$
Shape-preserving LADE models with fixed local LF shape provide the statistically preferred description of UV QLF evolution to z~7.5 over flexible alternatives based on AIC/BIC.