Dynamical History of Ly αclouds

Abstract

The clustering properties of Ly $\alpha$ lines are analysed using an intermediate resolution ($\sim 1\mathring{A}$) spectra of 67 QSOs compiled from the literature. The pair velocity correlation function indicates a weak excess in the velocity intervals up to $\mathrm{\Delta v}=600\mathrm{km}{\mathrm{s}}^{-1}$. The z-integrated probability distribution of interline spacings also confirms the excess in the low velocity intervals. The dependence of pair velocity correlation on redshift and equivalent width are investigated. The cross-correlation properties of Ly $\alpha$ clouds with metal line redshifts are analysed. We do not find any tendency of Ly $\alpha$ lines to cluster around metal line systems. Depedence of the cross-correlation on redshift and equivalent widths of Ly $\alpha$ clouds are investigated. Various implications of the results are discussed.

arXiv comment30 pages, Latex file (nofigure). Complete uuencoded Z-compressed postscript files of text as well as figures are available via anonymous ftp at ftp://iucaa.ernet.in/pub/anand/ (or 144.16.31.1); Accepted for publication in Astrophysical Journal. arXiv admin note: only first 15 pages available as paper was corrupted during original email submission.

Cited by in corpus (3)

• Semi analytic approach to understanding the distribution of neutral hydrogen in the universe: Comparison of simulations with observations
• Spitzer's View of the Candidate Cluster and Protocluster Catalog (CCPC)
• On the Small-Scale Clustering of Ly-alpha Forest Clouds