English

The He II Opacity of the Lyman-alpha Forest and the Intergalactic Medium

Astrophysics 2009-10-30 v1

Abstract

Based on the empirical formulas governing the distribution of Ly-a forest absorption, we use a Monte-Carlo technique to calculate the average HeII optical depth produced by these forest lines. A substantial contribution to HeII absorption arises from extremely tenuous regions of intergalactic gas that are beyond the observational limits for HI absorption.

Keywords

Cite

@article{arxiv.astro-ph/9711143,
  title  = {The He II Opacity of the Lyman-alpha Forest and the Intergalactic Medium},
  author = {Wei Zheng and Arthur F. Davidsen and Gerard A. Kriss},
  journal= {arXiv preprint arXiv:astro-ph/9711143},
  year   = {2009}
}

Comments

18 pages, including 4 figures To appear in A.J., February 1998