H_2 molecules in damped systems

R. Srianand; P. Petitjean; C. Ledoux

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arXiv · astro-ph/0109155

H_2 molecules in damped systems

R. Srianand·P. Petitjean·C. Ledoux

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Abstract

Damped Lyman alpha systems seen in the spectra of high-z QSOs arise in high-density neutral gas in which molecular hydrogen (H_2) should be conspicuous. Systematic searches to detect the H_2 lines redshifted into the Lyman alpha forest at <3400Åare now possible thanks to the unique capabilities of UVES on the VLT. Here we summarise the present status of our on going programme to search for H_2 in DLAs, discuss the physical conditions in the systems where H_2 is detected and the implications of non-detections.

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R. Srianand, P. Petitjean, C. Ledoux. 2001-09-10. H_2 molecules in damped systems. https://arxiv.org/abs/astro-ph/0109155

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