Reconstructing the intergalactic UV background with QSO absorption lines
نویسندگان
چکیده
منابع مشابه
Qso Absorption Lines from Qsos1
We present the results of a search for metal absorption lines in the spectra of background QSOs whose sightlines pass close to foreground QSOs. We detect Mg II λλ2796,2803 absorption in Sloan Digital Sky Survey (SDSS) spectra of four z > 1.5 QSOs whose lines of sight pass within 26−98 h−1 70 kpc of lower redshift (z ≃ 0.5 − 1.5) QSOs. The 100% [4/4 pairs] detection of Mg II in the background QS...
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High-resolution UV spectroscopy of low−z QSOs with the Space Telescope Imaging Spectrograph and the Far Ultraviolet Spectroscopic Explorer has indicated that O VI absorption-line systems provide a valuable probe of the low−z intergalactic medium. These observations and their implications are briefly reviewed. Though still uncertain due to the small sample, the number of O VI absorbers per unit ...
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We present a reanalysis of the He Lyα absorption towards the quasars HS 1700+6416 and HE 2347-4342 using new high S /N, optical observations. An alternative analysis method is applied, which fits the high quality, optical H data directly to the He spectrum. The results are compared to those inferred from standard line profile analyses. This new method enables us to derive redshift scale...
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In this paper, I will take a synoptic approach to determining the intergalactic infrared radiation field (IIRF). This approach draws on both the multi-TeV γ-ray observations and the infrared background observations and relates them via the semi-empirical modelling method of Malkan & Stecker. I discuss the evidence for an intergalactic infrared background obtained by an analysis of the HEGRA obs...
متن کاملOn the Origin of the Clustered Qso Metal Absorption Lines
Observations show that there is significant clustering of QSO metal absorption lines within the range of velocity dispersion between 200km/sec and 600 km/sec. With a reasonable supernova rate, it is shown that high velocity gases driven by SNe and/or strong stellar winds could explain the clustered absorptions, provided that QSO metal-line absorbers are galactic halos or dwarf galaxies. Rich cl...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2011
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201117080