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Related papers: SDSS J211852.96-073227.5: The first non-local, int…

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The narrow line Seyfert 1 (NLS1) IRAS 13224-3809 is the most X-ray variable active galactic nucleus (AGN), exhibiting 0.3-10 keV flux changes of over an order of magnitude within an hour. We report on the results of the 1.5 Ms 2016…

High Energy Astrophysical Phenomena · Physics 2018-08-16 M. L. Parker , W. N. Alston , D. J. K Buisson , A. C. Fabian , J. Jiang , E. Kara , A. Lohfink , C. Pinto

We report the results of the optical follow-up of a sample of $\gamma$-ray-emitting active galactic nuclei (AGN). New high-quality optical spectra were obtained using Gran Telescopio Canarias with Optical System for Imaging and low-…

We present a new method for the statistical investigation into the distributions of the angle beta between the radio axis and the normal to the galactic disk for a sample of Seyfert galaxies. We discuss how further observations of the…

Astrophysics · Physics 2009-10-30 C. J. Clarke , A. L. Kinney , J. E. Pringle

Before the launch of the Fermi satellite only two classes of Active Galactic Nuclei (AGN) were known to generate relativistic jets and thus to emit up to the gamma-ray energy range: blazars and radio galaxies, both hosted in giant…

High Energy Astrophysical Phenomena · Physics 2019-08-13 F. D'Ammando , M. Orienti , J. Finke , M. Giroletti , J. Larsson

We have used the VIMOS IFU to map the properties of the Seyfert 1.9 galaxy LEDA 135736. These maps reveal a number of interesting features including: an Extended Narrow Line Region detectable out to 9 kpc, an area of intense star formation…

Astrophysics · Physics 2009-11-13 J. Gerssen , D. J. Wilman , L. Christensen , R. G. Bower , V. Wild

As one of the drivers of feedback in active galactic nuclei (AGNs), the jets launched from supermassive black holes (SMBHs) are important for understanding the co-evolution of SMBHs and their host galaxies. However, the formation of AGN…

High Energy Astrophysical Phenomena · Physics 2023-06-06 Su Yao , S. Komossa

We present near--infrared (NIR) imaging of FBQS J164442.5+261913, one of the few $\gamma$--ray emitting Narrow Line Seyfert 1 ($\gamma-$NLSy1) galaxies detected at high significance level by $Fermi$--LAT. This study is the first…

Astrophysics of Galaxies · Physics 2017-01-18 A. Olguín-Iglesias , J. K. Kotilainen , J. León Tavares , V. Chavushyan , C. Añorve

1H 0323+342 is the nearest gamma-ray narrow-line Seyfert 1 galaxy (z=0.063). Its X-ray spectrum (0.3-10 keV) is characterised by significant spectral variability observed by many authors, with a backbone with photon index ~2 occasionally…

High Energy Astrophysical Phenomena · Physics 2025-12-02 Luigi Foschini

Although the properties of the narrow-line region (NLR) of active galactic nuclei(AGN) have been deeply studied by many authors in the past three decades, many questions are still open. The main goal of this work is to explore the NLR of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 L. Vaona , S. Ciroi , F. Di Mille , V. Cracco , G. La Mura , P. Rafanelli

Narrow-line Seyfert 1 galaxies (NLS1) are an intriguing subclass of active galactic nuclei. Their observed properties indicate low central black hole mass and high accretion rate. The extremely radio-loud NLS1 sources often show…

Astrophysics of Galaxies · Physics 2017-11-07 K. É. Gabányi , S. Frey , Z. Paragi , E. Järvelä , T. Morokuma , T. An , M. Tanaka , I. Tar

We present optical integral field spectroscopy for five $z<0.062$ narrow-line Seyfert 1 galaxies (NLS1s) host galaxies, probing their host galaxies at $\gtrsim 2-3$ kpc scales. Emission lines in the nuclear AGN spectra and the large-scale…

Astrophysics of Galaxies · Physics 2017-11-22 J. Scharwächter , B. Husemann , G. Busch , S. Komossa , M. A. Dopita

We present a follow-up study on a series of papers concerning the role of close interactions as a possible triggering mechanism of AGN activity. We have already studied the close (<100kpc/h) and the large scale (<1 Mpc/h) environment of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 E. Koulouridis , M. Plionis , V. Chavushyan , D. Dultzin , Y. Krongold , I. Georgantopoulos , J. Leon-Tavares

Active galactic nuclei (AGN) show a range of morphologies and dynamical properties, which are determined not only by parameters intrinsic to the central engine but also their interaction with the surrounding environment. We investigate the…

High Energy Astrophysical Phenomena · Physics 2022-08-16 Soham Mandal , Paul C. Duffell , Yuan Li

We present preliminary results of the analysis of optical spectra of two complementary samples of Seyfert galaxies. The first sample was extracted from a selection of the 4th Fermi Gamma-ray Large Area Telescope (4FGL) catalog, and consists…

Astrophysics of Galaxies · Physics 2023-11-06 Benedetta Dalla Barba , Marco Berton , Luigi Foschini , Giovanni La Mura , Amelia Vietri , Stefano Ciroi

We report the discovery of a local convergence of a jet cross section in the quasi-stationary jet feature in the gamma-ray-emitting narrow-line Seyfert 1 galaxy (NLS1) 1H 0323+342. The convergence site is located at approximately 7 mas…

Astrophysics of Galaxies · Physics 2018-04-25 Akihiro Doi , Kazuhiro Hada , Motoki Kino , Kiyoaki Wajima , Satomi Nakahara

The fine-scale structure and the kinematics of relativistic active galactic nuclei (AGN) jets have been studied by very-long-baseline interferometry at very high resolutions since 1998 at 2 cm wavelength for a sample of over a hundred radio…

Astrophysics · Physics 2014-11-18 Eduardo Ros

We present a multi-frequency study of PKS J1222$+$0413 (4C$+$04.42), currently the highest redshift $\gamma$-ray emitting narrow-line Seyfert 1 ($\gamma$-NLS1). We assemble a broad spectral energy distribution (SED) including previously…

We are compiling a new list of gamma-ray jetted active galactic nuclei (AGN), starting from the fourth catalog of point sources of the Fermi Large Area Telescope (LAT). Our aim is to prepare a list of jetted AGN with known redshifts and…

High Energy Astrophysical Phenomena · Physics 2021-10-06 L. Foschini , M. L. Lister , S. Antón , M. Berton , S. Ciroi , M. J. M. Marchã , M. Tornikoski , E. Järvelä , P. Romano , S. Vercellone , E. Dalla Bontà

SDSS J163401.94$+$480940.2 is a non-jetted radio-loud narrow-line Seyfert 1 (NLSy1) galaxy. Optical monitoring of this object was carried out in two intra-night sessions each $\geq$ 3 hrs with 3.6m DOT. Intra-night optical variability…

Astrophysics of Galaxies · Physics 2022-05-25 Vineet Ojha

The discovery of gamma-ray emission from 5 radio-loud narrow-line Seyfert 1 galaxies revealed the presence of a possible emerging third class of AGNs with relativistic jets, in addition to blazars and radio galaxies. The existence of…

High Energy Astrophysical Phenomena · Physics 2019-08-13 F. D'Ammando , M. Orienti , J. Finke , J. Larsson , M. Giroletti