English
Related papers

Related papers: Magnetic fields of active galactic nuclei and quas…

200 papers

We calculate the polarization of radiation from thick accretion disks with vertically averaged global magnetic field. The polarization arises as a result of the radiation scattering by free electrons in magnetized plasma of a disk. We…

Astrophysics · Physics 2007-05-23 Yu. N. Gnedin , N. A. Silant'ev , P. S. Shternin

In most of Seyfert-1 active galactic nucei (AGN) the optical linear continuum polarization degree is usually small (less than 1%) and the polarization position angle is nearly parallel to the AGN radio-axis. However, there are many types-1…

Astrophysics of Galaxies · Physics 2017-02-22 N. A. Silant'ev , Yu. N. Gnedin , M. Yu. Piotrovich , T. M. Natsvlishvili , S. D. Buliga

The article considers the optically thick accretion discs with the progressive increasing height. The surface is assumed to be the conical form. The radiation with considered wavelength emerges from an ring on the cone and is described by…

Solar and Stellar Astrophysics · Physics 2019-07-16 N. A. Silant'ev , G. A. Alekseeva , V. V. Novikov

We consider the integral light polarization from optically thick accretion disks. Basic mechanism is the multiple light scattering on free electrons (Milne's problem) in magnetized atmosphere. The Faraday rotation of the polarization plane…

Astrophysics of Galaxies · Physics 2009-08-20 N. A. Silant'ev , M. Yu. Piotrovich , Yu. N. Gnedin , T. M. Natsvlishvili

The strengths of magnetic fields in interstellar gas clouds are obtained through observations of the circular polarization of spectral line radiation. Irregularities in this magnetic field may be present due to turbulence, waves or perhaps…

Astrophysics · Physics 2009-10-31 W. D. Watson , D. S. Wiebe , R. M. Crutcher

We consider the influence of Faraday rotation in chaotic magnetic field on the intensity and linear polarization of multiple scattered radiation. All fluctuations are assumed as Gaussian type and isotropic. The values of magnetic field are…

Solar and Stellar Astrophysics · Physics 2019-01-23 N. A. Silant'ev , G. A. Alekseeva , Yu. K. Ananjevskaja

Contopoulos et al. recently argued that there is observational evidence for a preferred sense of the Faraday rotation-measure gradients across jets from active galactic nuclei (AGNs). Such behaviour could arise if there were a deterministic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Arieh Königl

Observations of AGNs and microquasars by ASCA, RXTE, Chandra and XMM-Newton indicate the existence of wide X-ray emission lines of heavy ionized elements in their spectra. The emission can arise in the inner parts of accretion discs where…

Astrophysics · Physics 2009-11-07 A. F. Zakharov , N. S. Kardashev , V. N. Lukash , S. V. Repin

Accretion discs are composed of ionized gas in motion around a central object. Sometimes, the disc is the source of powerful bipolar jets along its rotation axis. Theoretical models invoke the existence of a bipolar magnetic field crossing…

High Energy Astrophysical Phenomena · Physics 2011-12-23 Remi de Guiran , Jonathan Ferreira

The centre of our Milky Way harbours the closest candidate for a supermassive black hole. The source is thought to be powered by radiatively inefficient accretion of gas from its environment. This form of accretion is a standard mode of…

Calculations are performed for the linear polarization of starlight due to extinction by aligned dust grains when the starlight traverses a medium with irregular magnetic fields. This medium is intended to represent the optically thick…

Astrophysics · Physics 2009-10-31 D. S. Wiebe , W. D. Watson

Analytical models of axially symmetric thin disks of finite extension in presence of magnetic field are presented based on the well-known Morgan-Morgan solutions. The source of the magnetic field is cons\-tructed separating the equation…

Astrophysics of Galaxies · Physics 2016-04-11 Edinson Cardona-Rueda , Gonzalo García-Reyes

Total magnetic fields in spiral galaxies, as observed through their total synchrotron emission, are strongest (up to \simeq 30\mu G) in the spiral arms. The degree of radio polarization is low; the field in the arms must be mostly turbulent…

Astrophysics · Physics 2009-11-11 Rainer Beck

We point out that luminous magnetic flares, thought to occur in standard AGN accretion disks, cannot be located much higher than few pressure scale heights above the disk. Using this fact, we estimate the fraction of the disk surface…

Astrophysics · Physics 2009-11-06 Sergei Nayakshin , Demosthenes Kazanas

Within four nearby (d < 160 pc) molecular clouds, we statistically evaluate the structure of the interstellar magnetic field, projected on the plane of the sky and integrated along the line of sight, as inferred from the polarized thermal…

The X-ray spectra of Active Galactic Nuclei (AGN) are complex and vary rapidly in time as seen in recent observations. Magnetic flares above the accretion disk can account for the extreme variability of AGN. They also explain the observed…

Astrophysics · Physics 2009-11-11 R. W. Goosmann , B. Czerny , M. Mouchet , V. Karas , M. Dovciak , G. Ponti , A. Rozanska , A. -M. Dumont

Radio synchrotron emission, its polarization and its Faraday rotation are powerful tools to study the strength and structure of interstellar magnetic fields. The total intensity traces the strength and distribution of total magnetic fields.…

Astrophysics · Physics 2009-11-13 Rainer Beck

Observations of synchrotron radiation and the Faraday rotation of its polarized component allow us to investigate the magnetic properties of the diffuse interstellar medium in nearby galaxies, on scales down to roughly one hundred parsecs.…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-14 Andrew Fletcher

Magnetic fields play essential roles in protoplanetary disks. Magnetic fields in the disk atmosphere are of particular interest, as they are connected to the wind-launching mechanism. In this work, we study the polarization of the light…

Earth and Planetary Astrophysics · Physics 2022-08-24 Haifeng Yang , Zhi-Yun Li

The configuration of the regular magnetic field in M31 is deduced from radio polarization observations at the wavelengths 6, 11 and 20 cm. By fitting the observed azimuthal distribution of polarization angles, we find that the regular…

Astrophysics · Physics 2009-11-10 A. Fletcher , E. M. Berkhuijsen , R. Beck , A. Shukurov
‹ Prev 1 2 3 10 Next ›