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Related papers: Seyfert 2 Galaxies with Spectropolarimetric Observ…

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We present the spectrophotometric properties of a sample of 141 emission-line galaxies at redshifts in the range $0.2<z<1.0$ with a peak around $z\in[0.2,0.4]$. The analysis is based on medium resolution ($R\_{\mathrm{s}}=500-600$), optical…

We report on BeppoSAX broad band (0.1-100 keV) observations of bright Seyfert 2 galaxies and discuss the results in the framework of the unified theory of AGNs. The data are used to probe Nh distribution in type 2 objects and to identify…

Astrophysics · Physics 2007-05-23 L. Bassani , M. Cappi , G. Malaguti

We present XMM-Newton observations of four low-redshift Seyfert galaxies selected to have low host luminosities (M_g>-20 mag) and small stellar velocity dispersions (sigma_star<45 km/s), which are among the smallest stellar velocity…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 C. E. Thornton , A. J. Barth , L. C. Ho , J. E. Greene

We present high sensitivity polarimetric observations in 6 bands covering the 5.5-38 GHz range of a complete sample of 53 compact extragalactic radio sources brighter than 200 mJy at 20 GHz. The observations, carried out with the Australia…

We present near-infrared K- (1.9-2.5 micrometer) and L- (2.8-4.2 micrometer) band spectroscopy of 22 Seyfert nuclei. We use two methods to investigate the presence of nuclear starbursts: (1) the Polycyclic Aromatic Hydrocarbon (PAH)…

Astrophysics of Galaxies · Physics 2015-05-20 Nagisa Oi , Masatoshi Imanishi , Keisuke Imase

We discuss results from very long baseline interferometry (VLBI) observations of two Seyfert galaxies with double peaked emission lines in their SDSS optical spectra. Such AGN are potential candidates for the presence of binary black holes,…

Astrophysics of Galaxies · Physics 2015-09-01 P. Kharb , M. Das , S. Subramanian , Z. Paragi

We present a new accurate sample of narrow-line Seyfert 1 galaxies (NLS1s) in the southern hemisphere from the Six-degree Field Galaxy Survey (6dFGS). Based on the optical spectral features, 167 sources were classified as NLS1s. We derived…

Astrophysics of Galaxies · Physics 2018-09-19 S. Chen , M. Berton , G. La Mura , E. Congiu , V. Cracco , L. Foschini , J. H. Fan , S. Ciroi , P. Rafanelli , D. Bastieri

We present the combined Chandra and Swift-BAT spectral analysis of seven Seyfert 2 galaxies selected from the Swift-BAT 100-month catalog. We selected nearby (z<=0.03) sources lacking of a ROSAT counterpart and never previously observed…

High Energy Astrophysical Phenomena · Physics 2017-02-22 Stefano Marchesi , Marco Ajello , Andrea Comastri , Giancarlo Cusumano , Valentina La Parola , Alberto Segreto

We present 8.4 GHz VLA A-configuration observations of 87 sources from the mid-infrared-selected AGN sample of Rush et al (1993). These 0.25 arcsec resolution observations allow elongated radio structures tens of parsecs in size to be…

Astrophysics · Physics 2009-10-31 Andy Thean , Alan Pedlar , Marek J. Kukula , Stefi A. Baum , Christopher P. O'Dea

The broad band 0.1-200 keV spectra of a sample of 5 Seyfert 2 galaxies (NGC 7172, Mkn 3, NGC 2110, NGC 4507 and NGC 7674) have been measured within the first year of the $BeppoSAX$ Core program. All sources have been detected up to \~ 100…

We compare the emission at multiple wavelengths of an extended Seyfert galaxy sample, including both types of Seyfert nuclei. We use the Caltech Submillimeter Observatory to observe the CO J = 2-1 transition line in a sample of 45 Seyfert…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-17 R. R. Monje , A. W. Blain , T. G. Phillips

We show from modeling the Fe Kalpha line in the ASCA spectra of four X-ray bright narrow emission line galaxies (Seyfert types 1.9 and 2) that two equally viable physical models can describe the observed line profile. The first is discussed…

Astrophysics · Physics 2009-10-30 K. A. Weaver , C. S. Reynolds

We present near-infrared spectra with resolutions of lambda/dlambda~1200 in the emission lines of Pa-beta, [FeII] (1.2567um), Br-gamma, and H2 v=1-0S(1) of the nuclei and circumnuclear regions of the four Seyfert 2 galaxies Mk 1066, NGC…

Astrophysics · Physics 2009-11-06 R. A. Knop , L. Armus , K. Matthews , T. W. Murphy , B. T. Soifer

We present the results of an intermediate-resolution (1.5\AA) spectroscopic study of 17 X-ray luminous narrow emission-line galaxies previously identified in the Cambridge-Cambridge {\it ROSAT} Serendipity Survey and the {\it Einstein}…

Astrophysics · Physics 2015-06-24 B. J. Boyle , R. G. McMahon , B. J. Wiles , M. Elvis

In this lecture note, we make the case for new (spectro)polarimetric measurements of "changing-look" AGNs (CLAGNs), a subclass of the AGN family tree that shows long-term (months to years) large flux variability associated with the…

Astrophysics of Galaxies · Physics 2019-09-09 F. Marin , D. Hutsemékers , B. Agís González

A new sample of hard X-ray sources in the Galactic Plane is being revealed by the regular observations performed by the INTEGRAL satellite. The full characterization of these sources is mandatory to understand the hard X-ray sky. Here we…

Astrophysics · Physics 2007-05-23 J. A. Combi , M. Ribo , J. Marti , S. Chaty

Recent ROSAT studies of narrow-line Seyfert 1 galaxies revealed these objects (with FWHM $H_{\beta} \le 2000 km s^{-1}$) generally show steeper soft X-ray spectra than broad line Seyfert 1's and that there are no AGN with broad lines and…

Astrophysics · Physics 2007-05-23 Amri Wandel , Thomas Boller

We report long, pointed ROSAT HRI observations of the hyperluminous galaxies IRAS F00235+1024, F12514+1027, F14481+4454 and F14537+1950. Two of them are optically classified as Seyfert-like. No X-ray sources are detected at the positions of…

Astrophysics · Physics 2009-10-30 R. J. Wilman , A. C. Fabian , R. M. Cutri , C. S. Crawford , W. N. Brandt

Spatially resolved emission-line spectroscopy is a powerful tool to determine the physical conditions in the narrow-line region (NLR) of active galactic nuclei (AGNs). We recently used optical long-slit spectroscopy to study the NLRs of a…

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

We present a semi-empirical calibration between the metallicity ($Z$) of Seyfert 2 Active Galactic Nuclei and the $N2$=log([N II]$\lambda$6584/H$\alpha$) emission-line intensity ratio. This calibration was derived through the [O…

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