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Related papers: Extreme UV QSOs

200 papers

We report on high resolution spectra of the bright QSO HS0747+4259 (zem = 1.90, V = 15.8) observed to search for intermediate redshift OVI absorption systems. The spectra were obtained by means of the Space Telescope Imaging Spectrograph…

We have assembled a UV-flux selected sample of 82 early-type galaxies and collected additional information at other wavelengths. These data confirm a large spread of the UV-V color in the range 2 to 5. The spread in UV-V is accompanied by a…

Astrophysics · Physics 2009-11-07 J. M. Deharveng , A. Boselli , J. Donas

Ultraviolet spectrographs aboard the Hubble Space Telescope (HST) and the Far Ultraviolet Spectroscopic Explorer (FUSE) have proved their value as sensitive probes of the low-density intergalactic medium (IGM) at low redshifts (z < 0.1).…

Astrophysics · Physics 2007-05-23 J. Michael Shull

We present an analysis of the proximity effect in a sample of ten 2 A resolution QSO spectra of the Ly alpha forest at <z> = 2.9. Rather than investigating variations in the number density of individual absorption lines we employ a novel…

Astrophysics · Physics 2009-11-07 J. Liske , G. M. Williger

We present time-resolved FUV spectra of the dwarf novae SS Cyg and WX Hyi in quiescence from observations using the Hopkins Ultraviolet Telescope on the Astro-1 and Astro-2 Space Shuttle missions and the Goddard High Resolution Spectrograph…

The influence of a foreground QSO on the lyman a forest of another QSO with higher redshift has been investigated by analyzing the spectra of three such objects at redshifts $z=2 - 2.7$. This influence is not contaminated by any projection…

Astrophysics · Physics 2015-06-24 A. Fernandez-Soto , X. Barcons , R. Carballo , J. K. Webb

We analyze archived Chandra and XMM-Newton X-ray observations of 536 Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) quasars (QSOs) at 1.7 <= z <= 2.7 in order to characterize the relative UV and X-ray spectral properties of QSOs that…

Astrophysics · Physics 2009-11-13 Robert R. Gibson , W. N. Brandt , Donald P. Schneider

We present ultraviolet (UV) to near-infrared (NIR) observations and analysis of the nearby Type Ia supernova SN 2021fxy. Our observations include UV photometry from Swift/UVOT, UV spectroscopy from HST/STIS, and high-cadence optical…

Low state optical photometry of EF Eri during an extended low accretion state combined with GALEX near and far UV time-resolved photometry reveals a source of UV flux that is much larger than the underlying 9500K white dwarf, and that is…

We investigate the prospects of extending observations of high redshift QSOs to z>8 by means of a very wide-area near-infrared slitless spectroscopic survey, e.g. the planned survey with the European Space Agency's Euclid telescope. For any…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Nathan Roche , Paolo Franzetti , Bianca Garilli , Giovanni Zamorani , Andrea Cimatti , Emanuel Rossetti

We have analyzed the broad absorption line system of the bright (V=16.5) high-redshift (z=2.361) QSO SBS1542+541 using UV spectra from the HST FOS along with optical data from the MMT and the Steward Observatory 2.3m telescope. These…

[Abbreviated] Rest-frame UV emission lines probe physical parameters of the emitting star-forming galaxies and their environments. The strongest main UV line, Ly$\alpha$, has been instrumental in advancing the general knowledge of galaxy…

Recent studies of QSOs with ROSAT suggest the existence of a significant population of Soft X-ray Weak QSOs (SXW QSOs) where the soft X-ray flux is ~ 10-30 times smaller than in typical QSOs. As a first step in a systematic study of these…

Astrophysics · Physics 2008-11-26 W. N. Brandt , A. Laor , Beverley J. Wills

We present the results of the first spectroscopic follow-up of 132 optically blue UV-excess sources selected from the UV-excess survey of the Northern Galactic Plane (UVEX). The UV-excess spectra are classified into different populations…

Three high-redshift (z=2) and high luminosity (M_B < -28 mag for Ho = 50, qo=0.5) QSOs, two radio-quiet one radio-loud, were imaged in R, I and K bands. The luminosities, colours and sizes of the hosts overlap with those of actively…

Astrophysics · Physics 2007-05-23 I. Aretxaga , R. J. Terlevich , B. J. Boyle

We investigate whether the far-UV continuum of nearby radio galaxies reveals evidence for the presence of star forming or non-stellar components. If a UV excess due to an extra radiation component exists we compare this with other…

Astrophysics of Galaxies · Physics 2015-09-16 Hans R. de Ruiter , Paola Parma , Roberto Fanti , Carla Fanti

Using GALEX, UVOT and optical photometry, we explore the prevalence and strength of the UV-upturn in the spectra of quiescent early type galaxies in several nearby clusters. Even for galaxies with completely passive optical colours, there…

Astrophysics of Galaxies · Physics 2018-02-14 S. S. Ali , M. N. Bremer , S. Phillipps , R. De Propris

We report the first space-based very deep near-infrared continuum observations of a uniform sample of z = 6.5 galaxies with log(L(L_alpha)) = 42.5 - 43 erg/s selected from narrow-band line searches and with spectroscopically confirmed Ly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Lennox L. Cowie , Esther M. Hu , Antoinette Songaila

We use integral field spectroscopy with the Gemini North Telescope to detect probable fluorescent Ly-alpha emission from gas lying close to the luminous QSO PSS 2155+1358 at redshift 4.28. The emission is most likely coming not from…

Astrophysics · Physics 2009-11-11 Paul J. Francis , Sunsanee McDonnell

We present the discovery of a gravitationally lensed dust-reddened QSO at $z=2.517$ discovered in a survey for red QSOs by infrared selection. $Hubble~Space~Telescope$ imaging in the WFC3/IR F160W and F125W filters reveals a quadruply…

Astrophysics of Galaxies · Physics 2018-07-17 E. Glikman , C. E. Rusu , S. G. Djorgovski , M. J. Graham , D. Stern , T. Urrutia , M. Lacy , J. M. O'Meara
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