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Related papers: Magnetic fields in AGNs and microquasars

200 papers

Persistent activity of magnetars is associated with electric discharge that continually injects relativistic particles into the magnetosphere. Large active magnetic loops around magnetars must be filled with outflowing particles that…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Andrei M. Beloborodov

The extragalactic magnetic field could be detected by searching for signatures of the electromagnetic cascade initiated by high-energy photons on the intergalactic radiation and deflected by the field. This process produces a time delay and…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-04 Boris Stern , Igor Tkachev

The magnetar model involves an isolated neutron star with a very high magnetic field (B~10^14-10^15 G), and is invoked to explain the emission processes of two classes of sources, the Anomalous X-ray Pulsars (AXPs) and the Soft Gamma-Ray…

Astrophysics · Physics 2008-01-17 Diego Gotz

We present new Chandra X-ray Observatory and Hubble Space Telescope observations of eight optically selected broad-line AGN candidates in nearby dwarf galaxies ($z<0.055$). Including archival Chandra observations of three additional…

High Energy Astrophysical Phenomena · Physics 2017-02-15 Vivienne F. Baldassare , Amy E. Reines , Elena Gallo , Jenny E. Greene

Recent observations of several gamma-ray burst (GRB) afterglows have shown evidence for a large amount of X-ray line emitting material, possibly arising from ionized iron. A significant detection of an X-ray spectral feature, such as that…

Astrophysics · Physics 2009-11-07 David R. Ballantyne , Enrico Ramirez-Ruiz

We estimated the magnetic field strength at the event horizon for a sample of supermassive black holes (SMBHs) in active galactic nuclei (AGNs). Our estimates were made using the values of the inclination angles of the accretion disk to the…

High Energy Astrophysical Phenomena · Physics 2020-05-20 M. Yu. Piotrovich , A. G. Mikhailov , S. D. Buliga , T. M. Natsvlishvili

We determine the effect of intergalactic magnetic fields on the distribution of high energy gamma rays by performing three-dimensional Monte Carlo simulations of the development of gamma-ray-induced electromagnetic cascades in the…

High Energy Astrophysical Phenomena · Physics 2016-10-19 Rafael Alves Batista , Andrey Saveliev , Guenter Sigl , Tanmay Vachaspati

{Although there is considerable evidence supporting an ubiquitous magnetic field in solar/stellar photospheres, its impact in the determination of abundances has never been quantified. In this work we investigate whether the magnetic field…

Astrophysics · Physics 2009-11-13 J. M. Borrero

We discuss some topical issues related to the Fe K emission lines in AGNs. We show remarkable agreement between non-contemporaneous ASCA and Chandra grating data and explain why there has been terrible confusion about the ASCA and post-ASCA…

Astrophysics · Physics 2007-05-23 Tahir Yaqoob

Spectral features can arise by reflection of coronal X-rays on a black hole accretion disc. The resulting profile bears various imprints of strong gravitational field acting on the light emitting gas. The observed shape of the reflection…

High Energy Astrophysical Phenomena · Physics 2015-05-30 V. Sochora , V. Karas , J. Svoboda , M. Dovciak

We have found empirically that the radio loudness of AGN can be understood as function of both the X-ray and optical luminosity. This way of considering the radio loudness was inspired by the hardness-intensity diagrams for X-ray binaries,…

Astrophysics · Physics 2008-11-26 Sebastian Jester , Elmar Koerding , Rob Fender

We present a full set of model atmosphere equations for the accretion disk around a supermassive black hole irradiated by hard X-ray lamp of power-law spectral distribution. Model equations allow for multiple Compton scattering of radiation…

Astrophysics · Physics 2008-04-09 Agata Różańska , Jerzy Madej

We study the influence of the regular component of the Galactic magnetic field (GMF) on the arrival directions of ultra-high energy cosmic rays (UHECRs). We find that, if the angular resolution of current experiments has to be fully…

Astrophysics · Physics 2009-11-13 M. Kachelriess , P. D. Serpico , M. Teshima

One of the most important parameters in the XRB (X-ray background) synthesis models is the average efficiency of accretion onto SMBH (super-massive black holes). This can be inferred from the shape of broad relativistic Fe lines seen in…

Non-thermal magnetospheric processes in the vicinity of supermassive black holes have attracted particular attention in recent times. Gap-type particle acceleration accompanied by curvature and Inverse Compton radiation could in principle…

High Energy Astrophysical Phenomena · Physics 2017-12-18 Frank M. Rieger , Grigorios Katsoulakos

We analyze X-ray spectra and images of a sample of Seyfert 2 galaxies that unambiguously contain starbursts, based on their optical and UV characteristics. Although all sample members contain active galactic nuclei (AGNs), supermassive…

Astrophysics · Physics 2009-10-31 N. A. Levenson , K. A. Weaver , T. M. Heckman

Relativistic emission lines generated by thin accretion disks around rotating black holes are an important diagnostic tool for testing gravity near the horizon. The iron K-line is of special importance for the interpretation of the X-ray…

Astrophysics · Physics 2009-11-10 Andreas Mueller , Max Camenzind

Preliminary results from an X-ray spectral study of Seyfert 1 galaxies with ASCA and RXTE are presented. From an analysis of X-ray reprocessing features of Compton reflection and Fe K-alpha fluorescence, it is found that iron line strength…

Astrophysics · Physics 2009-10-31 K. A. Weaver

Magnetic fields have been observed on all scales in our Galaxy, from AU to kpc. With pulsar dispersion measures and rotation measures, we can directly measure the magnetic fields in a very large region of the Galactic disk. The results show…

Astrophysics · Physics 2009-01-01 Jinlin Han

Some modern models of neutron star evolution predict that initially large magnetic fields rapidly decay down to some saturation value $\sim {\rm few}\times 0^{13}$ G and weaker magnetic fields do not decay significantly (Pons). It is…

High Energy Astrophysical Phenomena · Physics 2012-02-14 A. Chashkina , S. B. Popov
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