相关论文: Polarization Insights for Active Galactic Nuclei
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…