Molecular Hydrogen in Damped Ly-alpha Systems: Spatial Distribution

Details Molecular Hydrogen in Damped Ly-alpha Systems: Spatial Distribution Molecular Hydrogen in Damped Ly-alpha Systems: Spatial Distribution

2003-03-21

arxiv.org/abs/astro-ph/0303495v1

Mon.Not.Roy.Astron.Soc. 341 (2003) L18

Astronomy and Astrophysics

Astrophysics

5 pages, 3 figures, 1 table, accepted by MNRAS Letter

Scientific paper

10.1046/j.1365-8711.2003.06648.x

To interpret H_2 quasar absorption line observations in Damped Ly-alpha clouds (DLAs), we model the H_2 spatial distribution within a DLA. Based on numerical simulations of disk structures with parameters similar to those derived for such absorbers, we calculate the H_2 distribution as a function of ultraviolet background (UVB) intensity and dust-to-gas ratio. For typical values of these two quantities we find that the area in which the H_2 fraction exceeds 10^{-6} (typical observational detection limit) only covers $\la 10$% of the disk surface, i.e. H_2 has a very inhomogeneous, clumpy distribution even at these low abundance levels. This explains the relative paucity of H_2 detections in DLAs. We also show the dependence of the covering fraction of H_2 on dust-to-gas ratio and UVB intensity and we comment on the physics governing the H_2 chemical network at high redshift.

Affiliated with

Also associated with

No associations

Rating

Molecular Hydrogen in Damped Ly-alpha Systems: Spatial Distribution does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Molecular Hydrogen in Damped Ly-alpha Systems: Spatial Distribution, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Molecular Hydrogen in Damped Ly-alpha Systems: Spatial Distribution will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-153729