English

H_2 molecules in damped systems

Astrophysics 2007-05-23 v1

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 <3400\AA 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 H_2 in DLAs, discuss the physical conditions in the systems where H_2 is detected and the implications of non-detections.

Keywords

Cite

@article{arxiv.astro-ph/0109155,
  title  = {H_2 molecules in damped systems},
  author = {R. Srianand and P. Petitjean and C. Ledoux},
  journal= {arXiv preprint arXiv:astro-ph/0109155},
  year   = {2007}
}

Comments

4 pages. To appear in the Proceedings of the XVII IAP Colloquium "Gaseous Matter in Galaxies and Intergalactic Space"