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Related papers: Broad NeVIII 774 Emission From Quasars

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We discuss high resolution VLT/UVES observations (FWHM ~ 6 km/s) from October 2002 (day ~5700 past explosion) of the shock interaction of SN 1987A and its circumstellar ring. A nebular analysis of the narrow lines from the unshocked gas…

By observing the near-infrared spectrum of the quasar PG 1116+215 at z = 0.176 and combining with the HST/FOS spectrum, we obtained the relative strengths of three permitted OI lines ({lambda}1304, {lambda}8446, and {lambda}11287) in a…

Astrophysics · Physics 2015-06-24 Yoshiki Matsuoka , Shinki Oyabu , Yumihiko Tsuzuki , Kimiaki Kawara , Yuzuru Yoshii

Using a thermal-chemical model for the generic T-Tauri disk of D'Alessio et al. (1999), we estimate the strength of the fine-structure emission lines of NeII and NeIII at 12.81 and 15.55 microns that arise from the warm atmosphere of the…

Astrophysics · Physics 2008-11-26 Alfred E. Glassgold , Joan R. Najita , Javier Igea

We present the results from XMM-Newton observations of the highly optically polarized broad absorption line quasar (BALQSO) CSO 755. By analyzing its X-ray spectrum with a total of ~3000 photons we find that this source has an X-ray…

Astrophysics · Physics 2008-11-26 O. Shemmer , W. N. Brandt , S. C. Gallagher , C. Vignali , Th. Boller , G. Chartas , A. Comastri

We present a study of NV absorption systems at 1.5 < z < 2.5 in the optical spectra of 19 QSOs. Our analysis includes both absorbers arising from the intergalactic medium as well as systems in the vicinity of the background quasar. We…

Astrophysics · Physics 2009-11-13 C. Fechner , P. Richter

The X-shooter instrument on the VLT was used to obtain spectra of seven moderate-redshift quasars simultaneously covering the spectral range 3000 Ang to 2.5 microns. At z ~ 1.5, most of the prominent broad emission lines in the ultraviolet…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Luis C. Ho , Paolo Goldoni , Xiao-Bo Dong , Jenny E. Greene , Gabriele Ponti

Infrared quasi-stellar objects (IR QSOs) are a rare subpopulation selected from ultraluminous infrared galaxies (ULIRGs) and have been regarded as promising candidates of ULIRG-to-optical QSO transition objects. Here we present NOEMA…

Astrophysics of Galaxies · Physics 2021-06-02 Qing-Hua Tan , Yu Gao , Emanuele Daddi , Xiao-Yang Xia , Cai-Na Hao , Alain Omont , Kotaro Kohno

We perform a systematic study of outflow in the narrow-line region (NLR) of active galactic nuclei (AGNs) at $z\sim0.4-0.8$ basing upon a large sample of $\sim900$ quasars at $z\sim 0.4-0.8$. The sample is extracted from the Sloan Digital…

Astrophysics of Galaxies · Physics 2018-01-10 J. Wang , D. W. Xu , J. Y. Wei

The Seyfert 1 galaxy Mrk841 was observed five times between 2001 and 2005 by the XMM-Newton X-ray observatory. The source is well known for showing spectral complexity in the variable iron line and in the soft X-ray excess. This paper…

High Energy Astrophysical Phenomena · Physics 2015-05-14 A. L. Longinotti , E. Costantini , P. O. Petrucci , C. Boisson , M. Mouchet , M. Santos-Lleo , G. Matt , G. Ponti , A. C. Goncalves

We present results from a 900 ks exposure of NGC 3783 with the High-Energy Transmission Grating Spectrometer on board the Chandra X-ray Observatory. The resulting X-ray spectrum has the best combination of signal-to-noise and resolution…

We have used composite spectra generated from more than 22000 QSOs observed in the course of the 2dF and 6dF QSO Redshift Surveys to investigate the relationship between the velocity width of emission lines and QSO luminosity. We find that…

Six XMM-Newton observations of the bright narrow line Seyfert 1, Mrk 110, from 2004-2020, are presented. The analysis of the grating spectra from the Reflection Grating Spectrometer (RGS) reveals a broad component of the He-like Oxygen…

High Energy Astrophysical Phenomena · Physics 2021-05-03 J. N. Reeves , D. Porquet , V. Braito , N. Grosso , A. Lobban

We study the rest-frame optical properties of 74 luminous (L_bol=10^46.2-48.2 erg/s), 1.5<z<3.5 broad-line quasars with near-IR (JHK) slit spectroscopy. Systemic redshifts based on the peak of the [OIII]5007 line reveal that redshift…

Astrophysics of Galaxies · Physics 2016-01-27 Yue Shen

I Zw 1 is the prototype narrow line quasar. We report here the results of our study of the UV emission of I Zw 1 using a high S/N (50-120) spectrum obtained with the HST FOS. The following main new results are obtained: 1. The Mg II and Al…

Astrophysics · Physics 2009-10-30 Ari Laor , Buell T. Jannuzi , Richard F. Green , Todd A. Boroson

We present the data and our analysis of MIR fine-structure emission lines detected in Spitzer/IRS high-res spectra of 202 local LIRGs observed as part of the GOALS project. We detect emission lines of [SIV], [NeII], [NeV], [NeIII],…

A long 280 ks observation of the Seyfert 1 galaxy NGC 3783 with XMM-Newton is reported. We focus on the oxygen line complex between 17 and 24 A as measured with the RGS spectrometers. Accurate absorption column densities and emission line…

Over the past 15 years, examples of exotic radio-quiet quasars with intrinsically weak or absent broad emission line regions (BELRs) have emerged from large-scale spectroscopic sky surveys. Here, we present spectroscopy of seven such weak…

We present measurements of the soft X-ray background (SXRB) O VII and O VIII intensity between $l = 120\degr$ and $l = 240\degr$, the first results of a survey of the SXRB using archival XMM-Newton observations. We do not restrict ourselves…

Astrophysics of Galaxies · Physics 2015-05-18 David B. Henley , Robin L. Shelton

This paper discusses the detection of P V 1118,1128 and other broad absorption lines (BALs) in archival HST spectra of the low-redshift BALQSO, PG 1254+047. The P V identification is secured by excellent redshift and profile coincidences…

Astrophysics · Physics 2014-10-13 Fred Hamann

We present evidence that the outflowing UV absorbers in Seyfert 1 galaxies arise primarily in their inner narrow (emission) line regions (NLRs), based on similarities in their locations, kinematics, and physical conditions. 1) Hubble Space…

Astrophysics · Physics 2009-11-10 D. M. Crenshaw , S. B. Kraemer