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Related papers: Polarization Insights for Active Galactic Nuclei

200 papers

Velocity-resolved reverberation mapping suggests that the broad-line regions (BLRs) of AGNs can have significant net inflow. We use the STOKES radiative transfer code to show that electron and Rayleigh scattering off the BLR and torus…

Astrophysics · Physics 2015-03-13 C. Martin Gaskell , Rene W. Goosmann

New tools from Infrared Space Observatory (ISO) mid-infrared spectroscopy have recently become available to determine the power sources of dust-obscured ultraluminous infrared galaxies (ULIRGs). We compare ISO classifications - starburst or…

Astrophysics · Physics 2009-10-31 D. Lutz , S. Veilleux , R. Genzel

Optical broad-band polarimetry is presented for near-infrared color-selected AGN classified QSOs based on their K-band luminosity. More than 10% of a sample of 70 QSOs discovered in the Two Micron All Sky Survey (2MASS) with J-K > 2 and M_K…

Astrophysics · Physics 2009-11-07 P. S. Smith , G. D. Schmidt , D. C. Hines , R. M. Cutri , B. O. Nelson

Some bright cD galaxies in cluster cooling flows have Thomson optical depths exceeding 0.01. A few percent of their luminosity is scattered and appears as diffuse polarized emission. We calculate the scattering process for different…

Astrophysics · Physics 2009-10-22 B. W. Murphy , D. F. Chernoff

Recent time-resolved spectral studies of a few Active Galactic Nuclei in hard X-rays revealed occultations of the X-ray primary source probably by Broad Line Region (BLR) clouds. An important open question on the structure of the…

Astrophysics of Galaxies · Physics 2015-06-19 G. Torricelli-Ciamponi , P. Pietrini , G. Risaliti , M. Salvati

Here we give an observational method for measurements of the equatorial scattering region radius using variability in the polarized broad lines in Type 1 active galactic nuclei (AGNs). The polarization in broad lines of Type 1 AGNs is…

Astrophysics of Galaxies · Physics 2020-04-15 E. S. Shablovinskaya , V. L. Afanasiev , L. Č. Popović

Population of levels of the hyperfine and fine split ground state of an atom is affected by radiative transitions induced by anisotropic radiation flux. Such aligned atoms precess in the external magnetic field and this affects properties…

Astrophysics · Physics 2007-05-23 Huirong Yan , A. Lazarian

We calculated the polarization degree of hydrogen Balmer broad emission lines from a number of active galactic nuclei (AGNs) with determined virial factors. The objects were selected from the sample presented by Decarli et al.(2008). In our…

Astrophysics of Galaxies · Physics 2017-03-27 M. Yu. Piotrovich , Yu. N. Gnedin , T. M. Natsvlishvili , S. D. Buliga

The physical nature of the X-ray/radio correlation of AGN is still an unsolved question. High angular resolution observations are necessary to disentangle the associated energy dynamics into nuclear and stellar components. We present…

Astrophysics · Physics 2014-11-18 Jens Zuther , Sebastian Fischer , Andreas Eckart

The measurements of the linear polarisation of visible light from quasars give strong evidence for large-scale coherent orientations of their polarisation vectors in some regions of the sky. We show that these observations can be explained…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-04 A. Payez , J. R. Cudell , D. Hutsemékers

We describe the results of a detailed study of the polarization properties of the broad H-alpha emission line in Type 1 Seyfert nuclei. Our analysis of these data points to a model in which the broad Balmer lines are emitted by a rotating…

Astrophysics · Physics 2007-05-23 Andy Robinson , David J. Axon , James E. Smith

We present the results of our multifrequency observations for 10 ultraluminous infrared galaxies (ULIRGs) made by the Karl G. Jansky Very Large Array at 1.4, 5.5, 9.0, and 14.0 GHz. Our sample is selected from ULIRGs whose active galactic…

Astrophysics of Galaxies · Physics 2021-05-12 Takayuki J. Hayashi , Yoshiaki Hagiwara , Masatoshi Imanishi

We present near-IR imaging polarimetry observations of the nucleus of Cygnus A, taken with the NICMOS camera of the HST at a wavelength of 2.0 microns.These maps reveal a highly collimated region of polarized emission straddling the nucleus…

A fraction of active galactic nuclei do not show the classical Seyfert-type signatures in their optical spectra, i.e. they are optically "elusive". X-ray observations are an optimal tool to identify this class of objects. We combine new…

The Unified Model of Active Galactic Nuclei (UMAGN) is a comprehensive theoretical framework aimed at elucidating the diverse observations of AGN, encompassing quasars and Seyfert galaxies. The Model attributes the observed variations to…

Astrophysics of Galaxies · Physics 2024-09-30 Leonardo de Lima Santos , Samuel Bueno Soltau

We conducted a Very Large Array survey of eleven low luminosity active galactic nuclei for linear and circular polarization at 8.4 GHz. We detected circular polarization in one source (M81*) and linear polarization in 3 sources. Sensitivity…

Astrophysics · Physics 2009-11-07 Geoffrey C. Bower , Heino Falcke , Richard R. Mellon

We use the sample of emission-line nuclei derived from a recently completed optical spectroscopic survey of nearby galaxies to quantify the incidence of local (z = 0) nuclear activity. Consistent with previous studies, we find detectable…

Astrophysics · Physics 2009-10-30 Luis C. Ho , Alexei V. Filippenko , Wallace L. W. Sargent

Synchrotron radiation from active galactic nuclei (AGN) is often highly polarized. We present a search for linear polarization with the Very Large Array (VLA) at 4.8 GHz and 8.4 GHz from the nearest AGN, Sagittarius A*. As a part of this…

Astrophysics · Physics 2009-10-31 Geoffrey C. Bower , Donald C. Backer , Jun-Hui Zhao , Miller Goss , Heino Falcke

Supermassive black holes in active galactic nuclei (AGNs) launch relativistic jets that shine through the entire electromagnetic spectrum. Blazars are a subclass of AGN where non-thermal radiation from the jet is strongly beamed, as the jet…

High Energy Astrophysical Phenomena · Physics 2024-11-26 Filippo Bolis , Emanuele Sobacchi , Fabrizio Tavecchio

We present an optical spectroscopic study of a 90% complete sample of 17 nearby ULIRGs with optical Seyfert nuclei, with the aim of investigating the nature of the nuclear warm gas outflows. A high proportion (94%) of our sample show…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 J. Rodriguez Zaurin , C. N. Tadhunter , M. Rose , J. Holt