Subaru High-Resolution Spectroscopy of Complex Metal Absorption Lines of the Quasar HS 1603+3820

Some intervening C IV absorbers in the Keck/HIRES spectrum of APM 0827+5255 give rise to absorption lines for which the observed optical depths for the doublet components are not in the expected 2 : 1 ratio. We model this effect as coverage of one line of sight to this gravitationally lensed quasar and perform a set of simulations to select a sample of lines for which our model provides an explanation for the effect. We use lines in this sample to obtain estimates for minimum absorber sizes from total coverage and the separations of the lines of sight for a range of lens redshifts, z1, and two cosmologies. We also obtain best estimates for overall sizes from a statistical “hit and miss” approach. For z1 = 0.7 our results set a lower limit to sizes of C IV absorbers of ~ 0.3 h−172 kpc (~ 0.5 h−172 kpc) for ΩM = 1, ΩA = 0 (ΩM = 0.3, ΩA = 0.7).

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Interstellar Matter with Very Large Telescopes

International Astronomical Union Colloquium ◽

10.1017/s0252921100108772 ◽

1984 ◽

Vol 79 ◽

pp. 675-678

Author(s):

J. Lequeux

Keyword(s):

High Resolution ◽

Absorption Lines ◽

High Resolution Spectroscopy ◽

Interstellar Matter ◽

Large Telescope ◽

Interstellar Absorption ◽

Near Ir ◽

Very Large Telescope ◽

Large Telescopes ◽

Diffuse Matter

Interstellar matter is certainly one of the fields where a very large telescope (VLT) will prove to be most fruitful. This includes (somewhat paradoxically, but this will be explained later) the study of extended emissions. I will now examine in turn the different domains of interest for a VLT.I. Neutral diffuse matterOptical and near IR observations will mainly contribute to this domain through high-resolution spectroscopy of interstellar absorption lines in the spectra of stars. These lines are resonant lines of atoms (NaI, KI, etc.) or ions (CaII, TiII, etc.) as well as of some molecules (CH+, CH, CN, CS+, C2 in the near IR). Clearly this kind of study is always photon - limited; a VLT will collect more photons than present telescopes, thus increase the possibilities considerably.

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On the Interpretation of QSO Absorption Lines

Symposium - International Astronomical Union ◽

10.1017/s007418090013699x ◽

1988 ◽

Vol 130 ◽

pp. 571-571

Author(s):

V. Müller ◽

J. P. Mücket ◽

S. Gottlöber ◽

H. J. Haubold

Keyword(s):

High Resolution ◽

Correlation Analysis ◽

Temperature Profile ◽

Absorption Spectra ◽

Significant Positive Correlation ◽

Radiation Transport ◽

Absorption Lines ◽

Positive Correlation ◽

Metal Absorption ◽

Inhomogeneous Temperature

OSO absorption spectra may offer a clue to the distribution of intervening matter clouds at z = 0 … 3. We tackle 1) the question of the occurrence of metal absorption lines of different ionisation levels in the same redshift systems by investigating the radiation transport through an inhomogeneous temperature profile; 2) the clustering properties of the lines of the Lyα forest by a correlation analysis of 9 published high-resolution QSO-spectra with the result of a certain contribution of metal absorption lines as well as marginally significant positive correlation regions ξ ≈ 0.3.

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