相关论文: The Origin and Evolution of \civ Baldwin Effect in…
The existence of an anti-correlation between the equivalent width (EW) of the narrow core of the iron Kalpha line and the luminosity of the continuum (i.e. the X-ray Baldwin effect) in type-I active galactic nuclei has been confirmed over…
We re-examine claims of redshift evolution in black hole-bulge scaling relations based on lensed quasars. In particular, we refine the black hole mass estimates using measurements of Balmer lines from near-infrared spectroscopy obtained…
Starting from the ~50000 quasars of the Sloan Digital Sky Survey for which MgII line width and 3000 A monochromatic flux are available, we aim to study the dependence of the mass of active black holes on redshift. We focus on the observed…
There are extremely luminous quasi stellar objects (QSOs) at high redshift which are absent at low redshift. The lower luminosities at low redshifts can be understood as the external manifestation of either a lower Eddington ratio or a…
We investigate the evolution of supermassive binary black holes (BBHs) in galaxies with realistic property distributions and the gravitational-wave (GW) radiation from the cosmic population of these BBHs. We incorporate a comprehensive…
Quasar broad emission lines are largely powered by photoionization from the accretion continuum. Increased central luminosity will enhance line emissivity in more distant clouds, leading to increased average distance of the…
The late-time integrated Sachs-Wolfe (ISW) imprint of $R\gtrsim 100~h^{-1}{\rm Mpc}$ super-structures is sourced by evolving large-scale potentials due to a dominant dark energy component in the $\Lambda$CDM model. The aspect that makes the…
We examine the UV emission from luminous early-type galaxies as a function of redshift. We perform a stacking analysis using Galaxy Evolution Explorer (GALEX) images of galaxies in the NOAO Deep Wide Field Survey (NDWFS) Bo\"otes field and…
We compile black hole (BH) masses for $\sim 60,000$ quasars in the redshift range $0.1 \lesssim z \lesssim 4.5$ included in the Fifth Data Release of the Sloan Digital Sky Survey (SDSS), using virial BH mass estimators based on the \hbeta,…
We investigate the continuum and emission line properties of 4576 SDSS quasars as a function of their optical/UV SEDs. The optical/UV color distribution of our sample is roughly Gaussian, but with a red tail; we distinguish between 1)…
Several works have studied the relation between X-ray, UV, and wind properties in broad absorption line quasars (BALQSOs), generally concluding that the formation of strong winds is tightly connected with the suppression of the ionizing…
We attempt to characterize the geometry of Broad Absorption Line (BAL) QSOs by studying a low redshift sample of 12 sources. We find that the majority of these sources are Population A quasars as defined in (broad H-beta FWHM > 4000 kms/s;…
We present composite UV spectra for low redshift Type 1 AGN binned to exploit the information content of the Eigenvector 1 (E1) parameter space. Composite spectra allow a decomposition of the CIV1549 line profile - one of the strongest…
We present host stellar velocity dispersion measurements for a sample of 88 broad-line quasars at 0.1<z<1 (46 at z>0.6) from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. High signal-to-noise ratio coadded spectra…
We report the discovery of rapid variations of a high-velocity CIV broad absorption line trough in the quasar SDSS J141007.74+541203.3. This object was intensively observed in 2014 as a part of the Sloan Digital Sky Survey Reverberation…
The Baldwin Effect, a negative correlation between emission-line equivalent width and luminosity in active galactic nuclei, is still of interest as a diagnostic of accretion physics nearly thirty years after its discovery. This review…
We present a universal linear correlation between the stellar mass and surface brightness (SB) of galaxies at 0.3<z<3, using a deep K-band selected catalog in the GOODS-North region. The correlation has a nearly constant slope, independent…
Luminous quasars are powerful targets to investigate the role of feedback from supermassive black-holes (BHs) in regulating the growth phases of BHs themselves and of their host galaxies, up to the highest redshifts. Here we investigate the…
Blueshifts - or, more accurately, blue asymmetries - in broad emission lines such as CIV $\lambda$1550 are common in luminous quasars and correlate with fundamental properties such as Eddington ratio and broad absorption line (BAL)…
We investigate the evolution of the Halpha equivalent width, EW(Halpha), with redshift and its dependence on stellar mass, taking advantage of the first data from the 3D-HST survey, a large spectroscopic Treasury program with the Hubble…