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Molecular hydrogen and the nature of damped Lyman-alpha systems

Patrick Petitjean·R. Srianand·Cédric Ledoux
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Abstract

We report results from our mini-survey for molecular hydrogen in eight high redshift damped Lyman-alpha (DLA) systems using the ESO Ultra-violet and Visible Spectrograph on the VLT. In addition, we investigate two systems using ESO public data. We include in the sample the only system where H2 was previously detected and studied at high-spectral resolution. Altogether our sample consists of eleven absorbers with 1.85 3000 K) implying a low formation rate of H2 onto dust grains. Therefore, most of the DLA systems arise in warm and diffuse neutral gas. (Abridged)

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Patrick Petitjean, R. Srianand, Cédric Ledoux. 2000-11-23. Molecular hydrogen and the nature of damped Lyman-alpha systems. https://arxiv.org/abs/astro-ph/0011437

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