The EUV variability of the luminous QSO HS 1700+6416

Abstract

We report on the first observations of variations in UV (intrinsic EUV 330 A) flux of the luminous QSO HS 1700+6416 (z=2.72) over a decade. The amplitude of variations increases from +/-0.1 mag in the optical (R) to up to a factor of 3 at 1250 A. This is apparently an extension of the increase in amplitude of variations towards shorter wavelengths observed with IUE in low z AGN (Paltani & Courvoisier, 1996) to the EUV. The time-scale for variations with the largest amplitudes is >= 1/2 yr to years. We briefly discuss the consequences of the observed variations on the ionizing metagalactic UV background.

arXiv comment4 pages, 3 figures

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Cited by in corpus (9)

• Reverberation Mapping of High-Luminosity Quasars: First Results
• The UV spectrum of HS1700+6416 II. FUSE observations of the HeII Lyman alpha forest
• Spatial fluctuations in the spectral shape of the UV background at 2<z<3 and the reionization of helium
• Exploratory X-ray Monitoring of Luminous Radio-Quiet Quasars at High Redshift: Initial Results
• The He II Post-Reionization Epoch: HST/COS Observations of the Quasar HS1700+6416
• Fluctuations of the intergalactic UV background towards two lines of sight
• Energy distribution of individual quasars from far-UV to X-rays: I. Intrinsic UV hardness and dust opacities
• The UV spectrum of HS1700+6416 I. Predicting the metal line content of the far UV spectrum
• SDSS J1138+3517: A quasar showing remarkably variable broad absorption lines