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Related papers: New Insights into the Quasar Type1/Type2 Dichotomy…

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We performed VLBA observations of the Broad Absorption Line Quasar FIRST\,J155633.8+351758, "the first radio loud BALQSO". Our observations at 15.3 GHz partially resolved a secondary component at positional angle (PA) $\approx 35^{\circ}$.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Cormac Reynolds , Brian Punsly , Christopher O'Dea

In a series of paper, it has been shown that the distribution of polarisation position angles for visible light from quasars is not random in extremely large regions of the sky. As explained in a recent article, the measurement of vanishing…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-09 A. Payez

Radio core dominance, usually measured by R, the rest frame ratio of core to lobe flux density, has been used as an indicator of Doppler boosting of quasars' radio jets and hence the inclination of the central engine's spin axis to the line…

Astrophysics · Physics 2009-10-28 Beverley J. Wills , M. S. Brotherton

In order to verify the existence of coherent orientations of quasars polarization vectors on very large scales, we have obtained new polarization measurements for a sample of quasars located in a given region of the three-dimensional…

Astrophysics · Physics 2009-10-31 D. Hutsemekers , H. Lamy

We present total-intensity and linear-polarization observations made with the Very Large Array at $\lambda$20 and 6 cm of a representative sample of 42 radio galaxies and quasars selected from the Molonglo Complete Sample. The sources have…

Astrophysics · Physics 2009-10-31 C. H. Ishwara-Chandra , D. J. Saikia , V. K. Kapahi , P. J. McCarthy

Radio emission is a good indicator of the jet power of radio-loud quasars, while the emission in broad-line can well represent the accretion disc radiation in quasars. We compile a sample of all sources of which the broad-line fluxes are…

Astrophysics · Physics 2009-10-31 Xinwu Cao , D. R. Jiang

VLA imaging at kiloparsec-scale resolution of sixteen core-dominated radio-loud QSOs is presented. Many objects appear to display variable radio emission and their radio morphologies are significantly smaller than those of steep-spectrum…

Astrophysics · Physics 2007-05-23 Peter D. Barthel , Marianne Vestergaard , Colin J. Lonsdale

We have compared the optical emission line ratios of type 2 quasars from Zakamska et al. with standard AGN photoionization model predictions, Seyfert 2s, HII galaxies, and narrow line FRII radio galaxies. Moderate to high ionization narrow…

We show that a model for radio source dynamics we had earlier proposed can readily reproduce the relationship between the radio power division separating the two Fanaroff-Riley classes of extragalactic radio sources and the optical…

Astrophysics · Physics 2009-11-06 Gopal-Krishna , Paul J. Wiita

A high degree of linear polarization measured in the optical emission is an important observational feature of blazars. It provides strong evidence of the presence of relativistic particles and magnetic field ordering in the non-thermal…

High Energy Astrophysical Phenomena · Physics 2025-03-17 K K Singh , A Singh , A Tolamatti , P J Meintjes , K K Yadav

A statistical model of the polarization of pulsar radio emission is used to derive the general statistics of a polarization vector's orientation angles. The theoretical distributions are compared with orientation angle histograms computed…

Astrophysics · Physics 2009-11-11 Mark M. McKinnon

Quasar feedback is suspected to play a key role in the evolution of massive galaxies, by removing or reheating gas in quasar host galaxies and thus limiting the amount of star formation. In this paper we continue our investigation of…

Astrophysics of Galaxies · Physics 2015-03-26 Guilin Liu , Nadia L. Zakamska , Jenny E. Greene

Using a homogenous sample of 38,208 quasars with a sky coverage of $4000 {\rm deg^2}$ drawn from the SDSS Data Release Five quasar catalog, we study the dependence of quasar clustering on luminosity, virial black hole mass, quasar color,…

The anisotropic nature of active galactic nuclei (AGN) is thought to be responsible for the observational differences between type-1 (pole-on) and type-2 (edge-on) nearby Seyfert-like galaxies. In this picture, the detection of emission…

Astrophysics of Galaxies · Physics 2014-04-10 F. Marin

The integrated spectrum of OH emission from late-type stars is often circularly polarized, by as much as 50% in some cases. While the spectra are partially polarized, the individual maser components revealed by VLBI are much more so. Using…

Astrophysics · Physics 2009-10-31 Stacy Palen

Three high-redshift (z=2) and high luminosity (M_B < -28 mag for Ho = 50, qo=0.5) QSOs, two radio-quiet one radio-loud, were imaged in R, I and K bands. The luminosities, colours and sizes of the hosts overlap with those of actively…

Astrophysics · Physics 2007-05-23 I. Aretxaga , R. J. Terlevich , B. J. Boyle

We study the correlations between the Very Long Baseline Array radio emission at 15 GHz, extended emission at 151 MHz, and optical nuclear emission at 5100 AA for a complete sample of 135 compact jets. We use the partial Kendall's tau…

Astrophysics of Galaxies · Physics 2015-03-13 T. G. Arshakian , J. Torrealba , V. H. Chavushyan , E. Ros , M. L. Lister , I. Cruz-González , J. A. Zensus

The host galaxies of six nearby QSOs are studied on the basis of high resolution HST optical images and spatially resolved VLT slit spectra. The gas ionization and velocity are mapped as a function of the distance to the central QSO. In the…

Astrophysics · Physics 2009-11-13 Y. Letawe , P. Magain , G. Letawe , F. Courbin , D. Hutsemékers

Using complete samples of steep-spectrum quasars, we present evidence for a correlation between radio and optical luminosity which is not caused by selection effects, nor caused by an orientation dependence (such as relativistic beaming),…

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