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Related papers: Magellan Spectroscopy of Low-Redshift Active Galac…

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We investigate the high-frequency radio spectra of twenty low-luminosity active galactic nuclei (LLAGNs) with compact radio cores. Our millimetre survey with the Nobeyama Millimetre Array (NMA) and analyses of submillimetre archival data…

Astrophysics · Physics 2009-11-13 A. Doi , S. Kameno , K. Kohno , K. Nakanishi , M. Inoue

We present a sample of 80 candidate strongly lensed galaxies with flux density above 100mJy at 500{\mu}m extracted from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS), over an area of 600 square degrees. Available imaging…

We present new near infrared spectroscopic measurements of the H_beta region for a sample of 29 luminous high redshift quasars. We have measured the width of H_beta in those sources, and added archival H_beta width measurements, to create a…

Astrophysics · Physics 2011-03-10 O. Shemmer , H. Netzer , R. Maiolino , E. Oliva , S. Croom , E. Corbett , L. di Fabrizio

We investigate spatially-resolved emission-line ratios in a sample of 219 galaxies ($0.6<z<1.3$) detected using the G102 grism on the \emph{Hubble Space Telescope} Wide Field Camera 3, taken as part of the CANDELS Ly$\alpha$ Emission at…

We investigate the relationship between the linewidths of broad Mg II \lambda2800 and Hbeta in active galactic nuclei (AGNs) to refine them as tools to estimate black hole (BH) masses. We perform a detailed spectral analysis of a large…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Jian-Guo Wang , Xiao-Bo Dong , Ting-Gui Wang , Luis C. Ho , Weimin Yuan , Huiyuan Wang , Kai Zhang , Shaohua Zhang , Hongyan Zhou

Motivated by theoretical expectations that Nuclear Star Clusters (NSCs) in galactic centers may provide a favorable environment for super-massive black holes to form and/or efficiently grow, we set out to measure the fraction of nearby…

High Energy Astrophysical Phenomena · Physics 2017-05-31 Adi Foord , Elena Gallo , Edmund Hodges-Kluck , Brendan P. Miller , Vivienne F. Baldassare , Kayhan Gultekin , Oleg Y. Gnedin

We present an optical spectroscopic atlas at intermediate resolution (8-15A) for 123 core-dominated radio-loud active galactic nuclei with relativistic jets, drawn from the MOJAVE/2cm sample at 15GHz. It is the first time that spectroscopic…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-13 Janet Torrealba , Vahram Chavushyan , Irene Cruz-González , Tigran G. Arshakian , Emanuele Bertone , Daniel Rosa-González

We combine emission line and X-ray luminosities for 45 sources from the Chandra Deep Field South (CDF-S), and seven HELLAS sources, to obtain a new sample of 52 X-ray selected type-II active galactic nuclei (AGNs). Eighteen of our sources…

Astrophysics · Physics 2009-11-11 Hagai Netzer , V. Mainieri , P. Rosati , Benny Trakhtenbrot

We present the results of a systematic search for gravitationally-lensed continuum Lyman break `drop-outs' beyond a redshift 7 conducted via very deep imaging through six foreground clusters undertaken with the Hubble and Spitzer Space…

Narrow spectral features in the 5--6 keV range were recently discovered in the X-ray spectra of a few active galactic nuclei. We discuss the possibility that these features are due to localized spots which occur on the surface of an…

Astrophysics · Physics 2007-05-23 M. Dovciak , S. Bianchi , M. Guainazzi , V. Karas , G. Matt

We report on a multiwavelength survey of a sample of 42 flat-spectrum radio-loud narrow-line Seyfert 1 galaxies (RLNLS1s). This is the largest known sample of this type of active galactic nucleus (AGN) to date. We found that 17% of sources…

The unified model of Seyfert galaxies suggests that there are hidden broad-line regions (HBLRs) in Seyfert 2 galaxies (S2s). However, there is increasing evidence for the appearance of a subclass of S2s lacking of HBLR (non-HBLR S2s). An…

Astrophysics · Physics 2008-11-26 E. -P Zhang , J. -M. Wang

We present ALMA observations at 233, 678, and 870 GHz of the Galactic Center black hole, Sagittarius A*. These observations reveal a flat spectrum over this frequency range with spectral index $\alpha \approx -0.3$, where the flux density…

We present the basic data for a large ground-based spectroscopic survey for z~3 ``Lyman break galaxies'' (LBGs), photometrically selected using rest-UV colors from very deep images in 17 high Galactic latitude fields. The total survey…

Astrophysics · Physics 2009-11-07 C. C. Steidel , K. L. Adelberger , A. E. Shapley , M. Pettini , M. Dickinson , M. Giavalisco

The SAGACE experiment consists of a mm/sub-mm telescope with a 3-m diameter primary mirror, coupled to a cryogenic multi-beam differential spectrometer. SAGACE explores the sky in the 100-760 GHz frequency range, using four…

We present spectroscopic redshifts for the first 466 X-ray and radio-selected AGN targets in the 2 deg^2 COSMOS field. Spectra were obtained with the IMACS instrument on the Magellan (Baade) telescope, using the nod-and-shuffle technique.…

In 2006 June, the obscured low luminosity active galactic nucleus in the nearby Seyfert 1.9 galaxy NGC 4258 was observed with Suzaku for ~ 100 ks. Utilizing the XIS and the HXD, the nucleus emission was detected over 2 to 40 keV range, with…

Astrophysics · Physics 2015-05-13 Shin'ya Yamada , Takeshi Itoh , Kazuo Makishima , Kazuhiro Nakazawa

A new low-dispersion objective-prism search for low-redshift (z<0.045) emission-line galaxies (ELG) has been carried out by the Universidad Complutense de Madrid with the Schmidt Telescope at the Calar-Alto Observatory. This is a…

Astrophysics · Physics 2009-10-31 O. Alonso , C. E. Garcia-Dabo , J. Zamorano , J. Gallego , M. Rego

We present a new empirical template for iron emission in active galactic nuclei (AGN) covering the $4000-5600$ A range. The new template is based on a spectrum of the narrow-line Seyfert 1 galaxy Mrk 493 obtained with the Hubble Space…

Astrophysics of Galaxies · Physics 2022-02-09 Daeseong Park , Aaron J. Barth , Luis C. Ho , Ari Laor

We present the results of our spectropolarimetric observations for a number of active galactic nuclei (AGNs) carried out at the 6-m telescope with the SCORPIO focal reducer. The derived wavelength dependences of the polarization have been…

Astrophysics of Galaxies · Physics 2011-04-20 V. L. Afanasiev , N. V. Borisov , Yu. N. Gnedin , T. M. Natsvlishvili , M. Yu. Piotrovich , S. D. Buliga
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