271 citations · 4.6k across the 192 of their papers we have counts for
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BAL effect in quasars due to source orientation
M. Sniegowska, M. H. Naddaf, M. L. Martinez-Aldama +3
We investigated a scenario where the presence of a broad absorption line (BAL) feature in quasars (QSOs) is contingent upon the line of sight being situated within an outflow cone…
Effect of extinction on quasar luminosity distances determined from UV and X-ray flux measurements
Michal Zajaček, Bożena Czerny, Narayan Khadka +4
In Khadka et al. (2023), a sample of X-ray-detected reverberation-mapped quasars was presented and applied for the comparison of cosmological constraints inferred using two well-es…
Wavelength-resolved reverberation mapping of intermediate redshift quasars HE 0413-4031 and HE 0435-4312: Dissecting Mg II, optical Fe II, and UV Fe II emission regions
Raj Prince, Michal Zajaček, S. Panda +24
We present the wavelength-resolved reverberation mapping (RM) of combined MgII and UV FeII broad-line emissions for two intermediate redshifts (z1), luminous quasars - HE 041…
Expectations for time-delay measurements in active galactic nuclei with the Vera Rubin Observatory
Bozena Czerny, Swayamtrupta Panda, Raj Prince +10
The Vera Rubin Observatory will provide an unprecedented set of time-dependent observations of the sky. The planned Legacy Survey of Space and Time (LSST) operating for 10 years wi…
Dusty plasma in active galactic nuclei
Bożena Czerny, Michal Zajaček, Mohammad-Hassan Naddaf +10
Since many years we know that dust in the form of the dusty-molecular torus is responsible for the obscuration in active galactic nuclei (AGN) at large viewing angles and thus for…
The Wind Dynamics of Super-Eddington Sources in FRADO
Mohammad-Hassan Naddaf, Bożena Czerny, Michal Zajaček
We perform non-hydrodynamical 2.5D simulations to study the dynamics of material above accretion disk based on the disk radiation pressure acting on dust. We assume a super-accreti…
Black-hole activity feedback across vast scales
Michal Zajaček, Bożena Czerny, Rainer Schödel +2
Both observational and theoretical studies of black-hole activity or active galactic nucleus (AGN) feedback have been ongoing since the first indication of supermassive black holes…
Accretion disks, quasars and cosmology: meandering towards understanding
Bozena Czerny, Shulei Cao, Vikram Kumar Jaiswal +11
As Setti & Woltjer noted back in 1973, quasars could be used to construct the Hubble diagram but the actual application was not that straightforward. It took years to implement the…
Monitoring AGNs with H Asymmetry. III. Long-term Reverberation Mapping Results of 15 Palomar-Green Quasars
Dong-Wei Bao, Michael S. Brotherton, Pu Du +42
In this third paper of the series reporting on the reverberation mapping (RM) campaign of active galactic nuclei with asymmetric H emission-line profiles, we present results for…
Modelling time delays from two reprocessors in active galactic nuclei
Vikram Kumar Jaiswal, Raj Prince, Swayamtrupta Panda +1
Context. Continuum time delays from accretion disks in active galactic nuclei (AGN) has been proposed long time ago as a tool for measuring distances to the monitored sources. Howe…
Spectropolarimetry and spectral decomposition of high-accreting Narrow Line Seyfert 1 galaxies
Marzena Śniegowska, Swayamtrupta Panda, Bożena Czerny +7
Narrow Line Seyfert 1 (NLSy1) galaxies have been shown to have high Eddington ratios and relatively small black hole masses. The measurement of the black hole masses is based on th…
Wavelength-resolved Reverberation Mapping of quasar CTSC30.10: Dissecting MgII and FeII emission regions
Raj Prince, Michal Zajaček, Bożena Czerny +20
We present the results of the reverberation monitoring aimed at MgII broad line and FeII pseudocontinuum for the luminous quasar CTS C30.10 (z = 0.90052) with the Southern African…
Mass loss rate of accretion disk in FRADO
Mohammad-Hassan Naddaf, Bozena Czerny
We have developed the 2.5D version of the basic physically motivated 1D model of Czerny & Hryniewicz (2011), i.e. Failed Radiatively Accelerated Dusty Outflow (FRADO) model. This m…
Radiation pressure on dust explains the Low Ionized Broad Emission Lines in Active Galactic Nuclei
Mohammad-Hassan Naddaf, Bozena Czerny
Broad emission lines are the most characteristic features in the spectra of active galaxies. They mostly show either a single-peaked or double-peaked profiles; and originate from a…
Linear Spectropolarimetric Analysis of Fairall 9 with VLT/FORS2
Bo-Wei Jiang, Paola Marziani, Đorđe Savić +10
The quasar Main Sequence (MS) appears to be an incredibly powerful tool to organize the diversity in large samples of type-1 quasars but the most important physical parameters gove…
Viewing angle observations and effects of evolution with redshift, black hole mass, and Eddington ratio in quasar based cosmology
Raj Prince, Krzysztof Hryniewicz, Swayamtrupta Panda +2
This study is focused on the observational measurement of the viewing angle of individual quasars by modeling the broadband quasar spectrum ranging from the infra-red (IR) to the s…
The picture of BLR in 2.5-D FRADO: Dynamics & Geometry
Mohammad-Hassan Naddaf, Bozena Czerny, Ryszard Szczerba
The dynamics of the Broad Line Region (BLR) in Active galaxies is an open question, direct observational constraints suggest a predominantly Keplerian motion, with possible traces…
Viewing angle effects in quasar application to cosmology
Raj Prince, Bozena Czerny, Agnieszka Pollo
The symmetry axes of active galactic nuclei (AGN) are randomly distributed in space but highly inclined sources are heavily obscured and are not seen as quasars with broad emission…
The CaFe Project: Optical FeII and Near-Infrared Ca II triplet emission in active galaxies. II. The driver(s) of the Ca II and Fe II and its potential use as a chemical clock
Mary Loli Martínez-Aldama, Swayamtrupta Panda, Bożena Czerny +3
In this second paper in the series, we carefully analyze the observational properties of the optical FeII and NIR CaII triplet in Active Galactic Nuclei, as well as the luminosity,…
Missing bright red giants in the Galactic center: A fingerprint of its once active state?
Michal Zajaček, Anabella Araudo, Vladimír Karas +5
In the Galactic center nuclear star cluster, bright late-type stars exhibit a flat or even a decreasing surface-density profile, while fainter late-type stars maintain a cusp-like…
Time Delay of MgII Emission Response for the Luminous Quasar HE 0435-4312: Towards Application of High-Accretor Radius-Luminosity Relation in Cosmology
Michal Zajaček, Bożena Czerny, Mary Loli Martinez-Aldama +21
Using the six years of the spectroscopic monitoring of the luminous quasar HE 0435-4312 () with the Southern African Large Telescope (SALT), in combination with the photo…
Broad He I 1.08 μm absorption from the obscurer in the active galaxy NGC 5548
Conor Wildy, Hermine Landt, Martin J. Ward +2
The nucleus of the active galaxy NGC 5548 was the target of two intensive spectroscopic monitoring campaigns at X-ray, ultraviolet (UV), and optical frequencies in 2013/14. These c…
Scatter Analysis Along the Multidimensional Radius-Luminosity Relations for Reverberation-Mapped Mg II Sources
Mary Loli Martínez-Aldama, Michal Zajaček, Bożena Czerny +1
The usage of the radius-luminosity (R-L) relation for the determination of black hole masses across the cosmic history as well as its application for cosmological studies motivates…
The multi-phase environment in the centre of Centaurus A
A. Borkar, T. P. Adhikari, A. Różańska +6
We study the multi-phase medium in the vicinity of the active galactic nucleus Centaurus A (Cen A). Combined high-resolution observations with the ALMA and Chandra observatories in…