English
Related papers

Related papers: Broad NeVIII 774 Emission From Quasars

200 papers

We have identified a broad absorption line (BAL) outflow in the HST/STIS spectrum of the quasar QSO B0254-3327B at velocity $v=-3200\text{ km s$^{-1}$}$. The outflow has absorption troughs from ions such as Ne VIII, Na IX, Si XII, and Ne V.…

Astrophysics of Galaxies · Physics 2024-02-22 Doyee Byun , Nahum Arav , Maryam Dehghanian , Gwen Walker , Gerard A. Kriss

We present the first grating-resolution X-ray spectra of the Seyfert 1 galaxy NGC 3783, obtained with the High Energy Transmission Grating Spectrometer on the Chandra X-ray Observatory. These spectra reveal many narrow absorption lines from…

We report the first mid-IR detection of highly disturbed ionized gas in the ultraluminous infrared galaxy IRAS F00183-7111. The gas, traced by the 12.81um [NeII] and 15.56um [NeIII] lines, spans a velocity range of-3500 to 3000 km/s with…

We present a high resolution (R~500) X-ray spectrum of the bright quasar H1821+643 (z=0.297), obtained in a 470 ksec Chandra observation. We search for X-ray absorption by highly ionized metal species, OVII and OVIII in particular, at the…

Astrophysics · Physics 2008-11-26 Smita Mathur , David Weinberg , Xuelei Chen , .

Recent observations of Broad Absorption Line (BAL) quasars demonstrated that the soft X-ray emission of these objects is extremely weak and convincing evidence for very strong absorption by a high column density (~ 10^23.5 cm^-2) was…

Astrophysics · Physics 2009-10-31 T. G. Wang , W. Brinkmann , W. Yuan , J. X. Wang , Y. Y. Zhou

We measured the metallicity Z in the broad emission line regions (BELRs) of 43 SDSS quasars with the strongest N IV] and N III] emission lines. These N-Loud QSOs have unusually low black hole masses. We used the intensity ratio of N lines…

High Energy Astrophysical Phenomena · Physics 2014-01-21 Neelam Dhanda Batra , Jack A. Baldwin

We present results from an analysis of FUSE and HST/STIS spectroscopy of the z_em=0.57 quasar PKS0405-123. We focus on the intervening metal-line systems identified along the sightline and investigate their ionization mechanism, ionization…

We report the detection of OVI 1031,1037 and NV 1238,1242 absorption in a system of "mini-broad" absorption lines (mini-BALs) previously reported to have variable CIV 1548,1550 in the quasar PG0935+417. The formation of these lines in an…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Paola Rodríguez Hidalgo , Fred Hamann , Patrick Hall

We studied the spectra of six $z \sim 2.2$ quasars obtained with the X-shooter spectrograph at the Very Large Telescope. The redshift of these sources and X-shooter's spectral coverage allow us to cover the rest spectral range $\sim1200 -…

We study the degree of chemical enrichment in the Broad Emission Line Regions (BELRs) of two QSOs with unusually strong nitrogen emission lines. The N V 1240/ C IV 1549 intensity ratio is often used as a metallicity indicator for QSOs. The…

Astrophysics · Physics 2015-06-24 Neelam Dhanda , Jack A. Baldwin , Misty C. Bentz , Patrick S. Osmer

The flux ratios of high-ionization lines are commonly assumed to indicate the metallicity of the broad emission line region in luminous quasars. When accounting for the variation in their kinematic profiles, we show that the NV/CIV,…

Astrophysics of Galaxies · Physics 2021-06-21 Matthew J. Temple , Gary J. Ferland , Amy L. Rankine , Marios Chatzikos , Paul C. Hewett

We present a detailed study of the optical and NIR emission and absorption line spectrum of the quasar SDSS J163345.22+512748.4. We discovered on the newly acquired NIR spectrum a highly meta-stable neutral helium broad absorption line…

Astrophysics of Galaxies · Physics 2022-04-01 Bo Liu , Hongyan Zhou , Xinwen Shu , Shaohua Zhang , Tuo Ji , Xiang Pan , Peng Jiang

We obtained far-ultraviolet spectra of the Seyfert 1 galaxy NGC 7469 using the FUSE on 1999 December 6. Our spectra cover the wavelength range 990-1187 A with a resolution of 0.05 A. We see broad emission lines of CIII, NIII, OVI, and HeII…

Astrophysics · Physics 2009-11-07 G. A. Kriss , A. Blustin , G. Branduardi-Raymont , R. F. Green , J. Hutchings , M. E. Kaiser

In the last few years, prominent high-ionization nebular emission lines (i.e., OIII], CIII], CIV, HeII) have been observed in the deep UV spectra of z~5-7 galaxies, indicating that extreme radiation fields characterize reionization-era…

Astrophysics of Galaxies · Physics 2019-06-12 Danielle A. Berg , John Chisholm , Dawn K. Erb , Richard Pogge , Alaina Henry , Grace M. Olivier

We used Spitzer/IRS spectroscopic data on 426 galaxies including quasars, Seyferts, LINER and HII galaxies to investigate the relationship among the mid-IR emission lines. There is a tight linear correlation between the [Ne V]14.3 um and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Miguel Pereira-Santaella , Aleksandar M. Diamond-Stanic , Almudena Alonso-Herrero , George H. Rieke

We present a catalog of 5039 broad absorption line (BAL) quasars (QSOs) in the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) QSO catalog that have absorption troughs covering a continuous velocity range >= 2000 km/s. We have fit…

We present the results of deep optical spectroscopic observations using the LRIS spectrograph on the Keck I 10-m telescope of three ultra-luminous X-ray sources (ULXs), Ho IX X-1; M81 X-6; and Ho II X-1. Our observations reveal the…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Dae-Sik Moon , Fiona A. Harrison , S. Bradley Cenko , Jamil A. Shariff

We characterise ionised gas outflows using a large sample of ~330 high-luminosity (45.5 < log(L_bol/erg s^-1) < 49.0), high-redshift (1.5 < z < 4.0) quasars via their [OIII]4960,5008 emission. The median velocity width of the [OIII]…

Astrophysics of Galaxies · Physics 2019-05-08 Liam Coatman , Paul C. Hewett , Manda Banerji , Gordon T. Richards , Joeseph F. Hennawi , J. Xavier Prochaska

We find line emission from the hydrogen- and/or helium-like ions of Ne, O, N and C in the low and short-on states of Her X-1, using the XMM-Newton Reflection Grating Spectrometer. The emission line velocity broadening is 200 < sigma < 500…

Astrophysics · Physics 2007-05-23 M. A. Jimenez-Garate , C. J. Hailey , J. W. den Herder , S. Zane , G. Ramsay

The [OIII] 5007 A emission line is the most common tracer of warm, ionized outflows in active galactic nuclei across cosmic time. JWST newly allows us to use mid-infrared spectral features at both high spatial and spectral resolution to…