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Related papers: Narrow Line Seyfert 1s in the IBISCO sample

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The high-ionization mid-IR lines, excited in the Narrow Line Regions (NLR) of Active Galactic Nuclei (AGN), barely affected by stellar excitation and dust extinction, trace the AGN bolometric power. We used the complete 12 micron sample of…

Astrophysics of Galaxies · Physics 2022-12-21 Luigi Spinoglio , Juan Antonio Fernandez-Ontiveros , Matthew A. Malkan

High-energy {\gamma}-rays, which are produced by powerful relativistic jets, are usually associated with blazars and radio galaxies. In the current active galactic nuclei (AGN) paradigm, such jets are almost exclusively launched from…

Astrophysics of Galaxies · Physics 2014-12-24 Emilia Järvelä , Anne Lähteenmäki , Jonathan León-Tavares

We present a detailed comparative systematic study using a sample of 221 Narrow-line Seyfert 1 (NLSy1) galaxies in comparison to a redshift matched sample of 154 Broad-line Seyfert 1 (BLSy1) galaxies based on their observations using ROSAT…

High Energy Astrophysical Phenomena · Physics 2020-06-24 Vineet Ojha , Hum Chand , Gulab Chand Dewangan , Suvendu Rakshit

We use a complete AGN sample (Ho et al. 1997) to study the environment of Seyferts, LINERs and HII galaxies. For each AGN we search for companions in the UZC redshift catalogue and compute local as well as large scale neighbour density and…

Astrophysics · Physics 2007-05-23 V. Zitelli , B. Kelm , P. Focardi , S. Montanaro

The 9-month Swift Burst Alert Telescope (BAT) catalog provides the first unbiased (log N_H < 24) look at local (<z> = 0.03) AGN. In this paper, we present the collected X-ray properties (0.3 - 12keV) for the 153 AGN detected. In addition,…

Astrophysics · Physics 2011-02-11 L. M. Winter , R. Mushotzky , C. S. Reynolds , J. Tueller

The INTEGRAL mission provides a large data set for studying the hard X-ray properties of AGN and allows testing of the unified scheme for AGN. We present analysis of INTEGRAL IBIS/ISGRI, JEM-X, and OMC data for 199 AGN supposedly detected…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 V. Beckmann , S. Soldi , C. Ricci , J. Alfonso-Garzón , T. J. -L. Courvoisier , A. Domingo , N. Gehrels , P. Lubinski , J. M. Mas-Hesse , A. A. Zdziarski

Indirectly resolving the line-emitting gas regions in distant Active Galactic Nuclei (AGN) requires both high-resolution photometry and spectroscopy (i.e. through reverberation mapping). Emission in AGN originates on widely different…

Astrophysics of Galaxies · Physics 2016-12-30 Beatriz Villarroel , Andreas J. Korn

The determination of the broad (0.1-100 keV) spectra of active galaxies is crucial for understanding and discriminating among emission models, for estimating the properties of the Comptonising/reflecting region around the central black hole…

High Energy Astrophysical Phenomena · Physics 2013-02-12 Manuela Molina , L. Bassani , A. Malizia , A. Bazzano , P. Ubertini , A. J. Bird

This paper presents the analysis of a statistically complete sample of 28 serendipitous X-ray sources selected in 82 pointed XMM-Newton fields down to a count-rate of 0.002 counts s^-1(4.5-7.5 keV energy band). This is the first sample…

We present results of an infrared-to-X-ray study of 76 bright soft X-ray selected Seyfert galaxies discovered in the ROSAT All-Sky Survey. These objects are characterized by steep X-ray spectra in the 0.2-2.0 keV bandpass with power law…

Astrophysics · Physics 2007-05-23 D. Grupe , K. Beuermann , H. -C. Thomas , K. Mannheim , H. H. Fink

We present near infrared ISAAC VLT observations of nine (0.01<z<0.06) Active Galactic Nuclei selected from the Hamburg/ESO Survey and the Veron-Cetty & Veron catalog. Hydrogen recombination lines Pa$\alpha$ and Br$\gamma$ are observed in…

Astrophysics · Physics 2009-11-11 S. Fischer , C. Iserlohe , J. Zuther , T. Bertram , C. Straubmeier , R. Schoedel , A. Eckart

We report the results of near infrared observations of 19 soft X-ray selected AGN. The goal of the observations was to search for strong, narrow Paschen-alpha or Brackett-gamma emission lines, as a sign of nuclear starbursts. We found…

Astrophysics · Physics 2009-11-07 D. Grupe , H. -C Thomas

In this work, we spectroscopically select narrow-line AGNs (NLAGNs) among the ~300 publicly available medium-resolution spectra of the Cosmic Evolution Early Release Science Survey (CEERS). Using both traditional and newly identified…

The masses of central supermassive black holes in a soft X-ray selected sample of the narrow-line Seyfert 1 galaxies (NLS1s) are estimated by some different methods to test their theoretical models. Apart from the methods using the H$\beta$…

Astrophysics · Physics 2009-11-10 W. Bian , Y. Zhao

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 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 study a sample of Narrow-line Seyfert 1 galaxies (NLS1) in their optical and radio features, in order to understand the differences between their radio silent, radio-loud and radio-quiet subclasses. We first show that the different…

Astrophysics of Galaxies · Physics 2018-08-15 Tullia Sbarrato , Massimo Dotti , Giancarlo Ghirlanda , Fabrizio Tavecchio

The soft X-ray band of many active galactic nuclei (AGNs) is affected by obscuration due to partially ionised matter crossing our line of sight. In this context, two past XMM-Newton observations (6 months apart) and a simultaneous…

The study of narrow-line Seyfert 1 galaxies (NLS1s) is now mostly limited to low redshift ($z<0.8$) because their definition requires the presence of the H$\beta$ emission line, which is redshifted out of the spectral coverage of major…

Astrophysics of Galaxies · Physics 2021-06-04 Suvendu Rakshit , C. S. Stalin , Jari Kotilainen , Jaejin Shin

We present a multi-waveband analysis of a 126 galaxy sub-sample of the 12 micron galaxy sample (12MGS), for which we have carried out a detailed X-ray spectral analysis of in a previous paper. We present optical activity classes and we…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Murray Brightman , Kirpal Nandra
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