ar X iv : a st ro - p h / 01 09 15 5 v 1 1 0 Se p 20 01 H 2 molecules in damped systems
نویسندگان
چکیده
Damped Lyα systems seen in the spectra of high-z QSOs arise in highdensity neutral gas in which molecular hydrogen (H2) should be conspicuous. Systematic searches to detect the H2 lines redshifted into the Lyα forest at < 3400Å are 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 H2 in DLAs, discuss the physical conditions in the systems where H2 is detected and the implications of non-detections.
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