Results 31 to 40 of about 2,579,062 (253)
Hints on the Broad Line Region Structure of Quasars at High and Low Luminosities
Open Astronomy, 2011 Quasars show a considerable spectroscopic diversity. However, the variety of quasar spectra at low redshifts is non-random: a principal component analysis applied to large samples customarily identifies two main eigenvectors. In this contribution we show
Marziani Paola +4 more
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Self-Consistent Dynamical Model of the Broad Line Region
Frontiers in Astronomy and Space Sciences, 2017 We develop a self-consistent description of the Broad Line Region based on the concept of a failed wind powered by radiation pressure acting on a dusty accretion disk atmosphere in Keplerian motion. The material raised high above the disk is illuminated,
Bozena Czerny +7 more
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Interpreting broad emission-line variations – I. Factors influencing the emission-line response [PDF]
Monthly Notices of the Royal Astronomical Society, 2014 21 pages, 17 figures, accepted for publication in MNRAS July ...
Goad, Michael R., Korista, K. T.
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Investigation of the Nature of the B[e] Star CI Cam in the Optical Range
GalaxiesThe B[e] phenomenon is observed in a wide range of stars at various evolutionary stages. Its nature remains uncertain. The B[e] phenomenon is defined as the simultaneous presence of low-excitation forbidden line emission and strong infrared excess in the
Elena A. Barsukova +3 more
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High Redshift Quasars, Emission Lines and ‘Cloudy’
Open Astronomy, 2011 I describe some of the outstanding “big picture” questions in quasar research and how the development of the plasma simulation code Cloudy is being guided to answer them.
Ferland Gary J.
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On the Intermediate Line Region in AGNs
Frontiers in Astronomy and Space Sciences, 2017 In this paper we explore the intermediate line region (ILR) by using the photoionisation simulations of the gas clouds present at different radial distances from the center, corresponding to the locations from BLR out to NLR in four types of AGNs. We let
Tek P. Adhikari +5 more
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X-ray emission of galaxies with emission lines [PDF]
Astronomical School’s Report, 2011 We built new sample of 315 SDSS galaxies which were detected as X-ray sources in 2XMM catalog. On the basis of distribution of relative intensities of emission lines NII [6583] and OIII [5007] we divided objects of the sample into starburst galaxies and galaxies with active nuclei. Also we found distributions of X-ray luminosities of these galaxies.
A. V. Tugay, A. A. Vasylenko
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A Photo-Ionization Method for Black Hole Mass Estimation in Quasars
Open Astronomy, 2011 Determining the masses of the central compact object believed to power all active galactic nuclei is relevant to our understanding of their evolution and of their inner workings.
Marziani Paola +3 more
doaj +1 more source
Calibrating emission lines as quasar bolometers [PDF]
Monthly Notices of the Royal Astronomical Society: Letters, 2011 Abstract Historically, emission lines have been considered a valuable tool for estimating the bolometric thermal luminosity of the accretion flow in active galactic nucleus, Lbol. We study the reliability of this method by comparing line strengths to the optical/ultraviolet continuum luminosity of Sloan Digital Sky Survey (SDSS) Data ...
Punsly, Brian, Zhang, Shaohua
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FEBS Letters, EarlyView.We present robust protocols for the preparation of supported lipid bilayers (SLBs) incorporating either Salmonella smooth LPS or outer membrane vesicles (OMVs). We use a combination of quartz crystal microbalance with dissipation (QCM‐D) and fluorescence microscopy to both characterize the SLBs of various compositions and to probe their interactions ...
Hudson P. Pace +6 more
wiley +1 more source