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Related papers: Accretion and jet power in active galactic nuclei

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The recent detection of high-energy gamma rays from Narrow-Line Seyfert 1 Galaxies has confirmed that also this type of active galactic nuclei can generate powerful relativistic jets. I outline the evolution of the knowledge in this…

High Energy Astrophysical Phenomena · Physics 2013-01-25 Luigi Foschini

We have conducted a multiwavelength survey of 42 radio loud narrow-1ine Seyfert 1 galaxies (RLNLS1s), selected by searching among all the known sources of this type and omitting those with steep radio spectra. We analyse data from radio…

We construct samples of jetted active galactic nuclei (AGNs) with low-frequency radio data from the recent released TGSS AD1 catalog at 150 MHz. With these samples, we compare the properties of jet power for blazars, radio-loud narrow-line…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-17 Xu-Liang Fan , Qingwen Wu

The discovery of high-energy (E>100 MeV) gamma rays from Narrow-Line Seyfert 1 Galaxies (gamma-NLS1s) has confirmed the presence of powerful relativistic jets in this class of active galactic nuclei (AGN). Although the jet emission is…

High Energy Astrophysical Phenomena · Physics 2012-04-23 Luigi Foschini

We discuss the relation between the power carried by relativistic jets and the nuclear power provided by accretion, for a group of blazars including FSRQs and BL Lac objects. They are characterized by good quality broad band X-ray data…

Astrophysics · Physics 2009-11-07 Laura Maraschi , Fabrizio Tavecchio

We present evidence in favour of a link between the luminosity radiatively dissipated in the central engine of radio-loud Active Galactic Nuclei and the kinetic power in their jets. This piece of evidence is based on the relation we find…

Astrophysics · Physics 2015-06-24 Annalisa Celotti , Paolo Padovani , Gabriele Ghisellini

Several narrow-line Seyfert 1 galaxies (NLS1s) have now been detected in gamma rays, providing firm evidence that at least some of this class of active galactic nuclei (AGN) produce relativistic jets. The presence of jets in NLS1s is…

We recently argued (Meyer 2011) that the collective properties of radio loud active galactic nuclei point to the existence of two families of sources, one of powerful sources with single velocity jets and one of weaker jets with significant…

High Energy Astrophysical Phenomena · Physics 2011-11-22 Markos Georganopoulos , Eileen T. Meyer , Giovanni Fossati , Matthew L. Lister

Collimated outflows (jets) appear to be a ubiquitous phenomenon associated with the accretion of material onto a compact object. Despite this ubiquity, many fundamental physics aspects of jets are still poorly understood and constrained.…

High Energy Astrophysical Phenomena · Physics 2017-02-15 Gustavo Romero , Markus Boettcher , Sera Markoff , Fabrizio Tavecchio

Most of the electromagnetic output of blazars (BL Lac objects and Flat Spectrum Radio Quasars) comes out in the gamma-ray band, making the Large Area Telescope [0.1-100 GeV] onboard the Fermi satellite and the Cherenkov telescopes crucial…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 G. Ghisellini

The properties of relativistic radio jets are thought to be closely connected with the properties of accretion disks in active galactic nuclei. We explore this issue using a sample of 35 blazars with very-long baseline observations, for…

Astrophysics · Physics 2009-11-10 Jian-Min Wang , Bin Luo , Luis C. Ho

In 2008, the Fermi Gamma-ray Space Telescope has revealed - for the first time - high-energy (E > 100 MeV) gamma rays from a few Narrow-Line Seyfert 1 Galaxies (NLS1s). Later, in 2009 and 2010, two multifrequency campaigns on one of these…

High Energy Astrophysical Phenomena · Physics 2013-10-22 Luigi Foschini

Radio-loud Narrow-line Seyfert 1 (NLS1) galaxies are unique probes of the formation of powerful radio jets at extreme (near-Eddington) accretion rates and low black hole masses, in a regime very different from classical blazars and,…

Astrophysics of Galaxies · Physics 2018-08-07 S. Komossa

Narrow-line Seyfert 1 galaxies (NLS1s) are active galactic nuclei (AGN) recently identified as a new class of $\gamma$-ray sources. The high energy emission is explained by the presence of a relativistic jet observed at small angles, just…

I provide a short review of the properties of Narrow-line Seyfert 1 (NLS1) galaxies across the electromagnetic spectrum and of the models to explain them. Their continuum and emission-line properties manifest one extreme form of Seyfert…

Astrophysics · Physics 2007-10-18 S. Komossa

Based on broadband spectral energy distribution (SEDs), we estimate the jet physical parameters of 1392 $\gamma$-ray-loud active galactic nuclei (AGNs), the largest sample so far. The (SED) jet power and magnetization parameter are derived…

High Energy Astrophysical Phenomena · Physics 2018-05-02 Liang Chen

The recent discovery by Fermi/LAT of high-energy (E>100 MeV) gamma rays from Narrow-Line Seyfert 1 Galaxies (NLS1s) made evident the existence of a third class of gamma-ray emitting Active Galactic Nuclei (AGN), after blazars and radio…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Luigi Foschini

Our understanding of the unification of jetted AGN has evolved greatly as jet samples have increased in size. Here, based on the largest-ever sample of over 2000 well-sampled jet spectral energy distributions, we examine the synchrotron…

Astrophysics of Galaxies · Physics 2021-05-12 Mary Keenan , Eileen T. Meyer , Markos Georganopoulos , Karthik Reddy , Omar J. French

In recent work, we have identified two sub-populations of radio-loud AGN which appear to be distinguished by jet structure, where low-efficiency accreting systems produce `weak' jets which decelerate more rapidly than the `strong' jets of…

High Energy Astrophysical Phenomena · Physics 2012-05-04 Eileen T. Meyer , Giovanni Fossati , Markos Georganopoulos , Matthew L. Lister

To constrain models of the jet-disc connection, we explore Eddington ratios reported in Foschini (2011) and interpret them in relation to the values in Sikora et al. across the active galactic nuclei population from radio loud quasars,…

High Energy Astrophysical Phenomena · Physics 2013-07-31 David Garofalo
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