Molecular Hydrogen in high redshift Damped Lyman-α systems
Author: Petitjean, Patrick
Source: Astrophysics and Space Science, Volume 281, Numbers 1-2, July 2002 , pp. 467-470(4)
Abstract:I describe briefly the status of an ongoing mini-survey for molecular hydrogen in high-redshift Damped Lyman-α systems using UVES at the VLT. H2 is detected in about 30% of the cases. When H2 is not detected the molecular fraction f = 2N(H2)/(2N(H2)+N(HI) is smaller than 10-5. Therefore, most of the DLA systems arise in warm (T > 3000 K) and diffuse neutral gas embedded in a strong UV flux. The very recent detection of HD molecules in a Damped Lyman-α system at z abs = 2.337 demonstrates the possibility to discuss the high redshift chemistry.
Document Type: Research Article
Affiliations: Email: email@example.com
Publication date: July 1, 2002