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Related papers: Seyfert 2 galaxies with unusually wide nebular lin…

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We present a study of reddening and absorption towards the Narrow Line Regions (NLR) in active galactic nuclei (AGN) selected from the Revised Shapley-Ames, 12mu, and Swift/Burst Alert Telescope samples. For the sources in host galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 S. B. Kraemer , H. R. Schmitt , D. M. Crenshaw , M. Melendez , T. J. Turner , M. Guainazzi. , R. F. Mushotzky

Type 2 active galactic nuclei (AGN) show signatures of accretion onto a supermassive black hole through strong, high-ionization, narrow emission lines extended on scales of 100s to 1000s of parsecs, but they lack the broad emission lines…

High Energy Astrophysical Phenomena · Physics 2022-09-21 M. Lynne Saade , Murray Brightman , Daniel Stern , Matthew A. Malkan , Javier A. Garcia

This paper contains a list of new AGN candidates identified from the examination of 3500 optical spectra contained in the database of the Southern Sky Redshift Survey Extension (SSRS2). The classification of galaxies was done using standard…

Astrophysics · Physics 2007-05-23 M. A. G. Maia , J. A. Suzuki , L. N. da Costa , C. N. A. Willmer , C. Rite

We present the results of a campaign of simultaneous X-ray and optical observations of `true' Type 2 Seyfert galaxies candidates, i.e. AGN without a Broad Line Region (BLR). Out of the initial sample composed by 8 sources, one object,…

X-ray unabsorbed Seyfert 2 galaxies appear to have X-ray absorption column densities that are too low (NH < 10^22 cm-2) to explain the absence of broad emission lines in their optical spectra, challenging the standard AGN unification model.…

High Energy Astrophysical Phenomena · Physics 2011-05-25 Xing-Xing Huang , Jun-Xian Wang , Ying Tan , Huan Yang , Ya-Fang Huang

We present the results of a long-term (1999--2010) spectral optical monitoring campaign of the active galactic nucleus (AGN) Ark 564, which shows a strong Fe II line emission in the optical. This AGN is a narrow line Seyfert 1 (NLS1)…

X-ray spectral features which are unusually strong in many Narrow-Line Seyfert galaxies are found to be consistent with reflection from strongly ionized matter, providing further evidence of a high accretion rate in these objects and…

Astrophysics · Physics 2009-10-31 K. Pounds , S. Vaughan

From the literature, we construct from literature a sample of 25 Seyfert 2 galaxies (S2s) with a broad line region detected in near infrared spectroscopy and 29 with NIR BLR which was detected. We find no significant difference between the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Hong-bing Cai , Xin-Wen Shu , Zhen-Ya Zheng , Jun-xian Wang

We have compiled a list of 83 objects classified as Narrow-Line Seyfert 1 galaxies (NLS1s) or known to have a broad Balmer component narrower than 2000 km/s. Out of these, 19 turned out to have been spectroscopically misidentified in…

Astrophysics · Physics 2009-11-06 M. -P. Veron-Cetty , P. Veron , A. C. Goncalves

We present the second and final data release of the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). Data are presented for 63 new galaxies not included in the first data release, and we provide 2D emission-line fitting…

We present spectra of 6 type 1 Seyfert galaxies, 2 Seyfert 2, a starburst galaxy and a compact narrow line radiogalaxy, taken in two spectral ranges centered around the near--IR CaII triplet (CaT) (at ~8600 Angstroms), and the Mgb stellar…

Astrophysics · Physics 2009-10-31 L. Jimenez-Benito , A. I. Diaz , R. Terlevich , E. Terlevich

We present modeling and interpretation of the continuum and emission lines for a sample of 51 unobscured Type 1 active galactic nuclei (AGN). All of these AGNs have high quality spectra from both XMM-Newton and Sloan Digital Sky Survey…

High Energy Astrophysical Phenomena · Physics 2015-05-30 C. Jin , M. Ward , C. Done , J. M. Gelbord

A sample of X-ray and optically selected narrow emission-line galaxies (769 sources) from the 3XMM catalogue cross-correlated with SDSS (DR9) catalogue has been studied. Narrow-emission line active galactic nuclei (AGN; type-2) have been…

High Energy Astrophysical Phenomena · Physics 2016-10-19 Estelle Pons , Mike G. Watson

We map narrow-line regions (NLRs) of 11 nearby Seyfert 2 galaxies with the optical integral-field spectrograph OASIS mounted at CFHT. We model emission-line profiles of 5 forbidden-line doublets and 2 Balmer lines, correcting for the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Ivana Stoklasová , Pierre Ferruit , Eric Emsellem , Bruno Jungwiert , Emmanuel Pécontal , Sebastian F. Sánchez

We present an analysis of the active galaxy SDSS J131642.90+175332.5, which is remarkable because all of its narrow emission lines are double-peaked, and because it additionally shows an extra broad component (FHWM ~ 1400 km/s) in most of…

Astrophysics of Galaxies · Physics 2015-05-14 Dawei Xu , S. Komossa

We provide a comprehensive census of the near-Infrared (NIR, 0.8-2.4 $\mu$m) spectroscopic properties of 102 nearby (z < 0.075) active galactic nuclei (AGN), selected in the hard X-ray band (14-195 keV) from the Swift-Burst Alert Telescope…

This work studies the optical emission line properties and physical conditions of the narrow line region (NLR) of seven narrow-line Seyfert 1 galaxies (NLS1). Our results show that the flux carried out by the narrow component of H-beta is,…

Astrophysics · Physics 2009-10-31 A. Rodriguez-Ardila , L. Binette , M. G. Pastoriza , C. J. Donzelli , .

While [OIII] narrow-band imaging is commonly used to measure the size of the narrow-line regions (NLRs) in active galactic nuclei (AGNs), it can be contaminated by emission from surrounding starbursts. Recently, we have shown that long-slit…

Astrophysics · Physics 2009-11-11 Nicola Bennert , Bruno Jungwiert , Stefanie Komossa , Martin Haas , Rolf Chini

We have analyzed new and archival IUE observations of narrow-line Seyfert 1 galaxies (NLS1) in order to revise the ultraviolet (UV) properties of this sub-group of Active Galactic Nuclei (AGN). We have found broad wings in the strongest UV…

Astrophysics · Physics 2007-05-23 Pedro M. Rodriguez-Pascual , J. Miguel Mas-Hesse , Maria Santos-Lleo

Line profiles can provide fundamental information on the physics of active galactic nuclei (AGN). In the case of narrow-line Seyfert 1 galaxies (NLS1s) this is of particular importance since past studies revealed how their permitted line…

Astrophysics of Galaxies · Physics 2020-01-29 M. Berton , I. Björklund , A. Lähteenmäki , E. Congiu , E. Järvelä , G. Terreran , G. La Mura