Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Quick Search
My eDoc
Session History
Support Wiki
Direct access to
document ID:

          Institute: MPI für Astrophysik     Collection: Cosmology     Display Documents

ID: 13518.0, MPI für Astrophysik / Cosmology
Statistics of neutral regions during hydrogen reionization
Authors:Nusser, A.; Benson, A. J.; Sugiyama, N.; Lacey, C.
Date of Publication (YYYY-MM-DD):2002-12-01
Title of Journal:The Astrophysical Journal
Journal Abbrev.:Astrophys. J.
Issue / Number:2
Start Page:L93
End Page:L96
Review Status:Peer-review
Audience:Experts Only
Abstract / Description:We present predictions for two statistical measures of the hydrogen reionization process at high redshift. The first statistic is the number of neutral segments identified in spectra of high-redshift QSOs as a function of their length. The second is the cross-correlation of neutral regions with possible sources of ionizing radiation. These independent probes are sensitive to the topology of the ionized regions. If reionization proceeded from high- to low-density regions, then the cross-correlation will be negative, while if voids were ionized first we expect a positive correlation and a relatively small number of long neutral segments. We test the sensitivity of these statistics for reionization by stars in high- redshift galaxies. The flux of ionizing radiation emitted from stars is estimated by identifying galaxies in an N-body simulation using a semianalytic galaxy formation model. The spatial distribution of ionized gas is traced in various models for the propagation of the ionization fronts. A model with ionization proceeding from high- to low-density regions is consistent with the observations of Becker et al., while models in which ionization begins in the lowest density regions appear to be inconsistent with the present data. Further data are required to confirm this result.
Free Keywords:cosmology : observations; cosmology : theory; dark matter; intergalactic medium; large-scale structure of universe; quasars : absorption lines
External Publication Status:published
Document Type:Article
Communicated by:N. N.
Affiliations:MPI für Astrophysik
External Affiliations:Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel; Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel; Technion Israel Inst Technol, Space Sci Inst, IL-32000 Haifa, Israel; CALTECH, Pasadena, CA 91125 USA; Natl Astron Observ, Div Theoret Astrophys, Mitaka, Tokyo 1818588, Japan; Max Planck Inst Astrophys, D-85741 Garching, Germany; Scuola Int Super Studi Avanzati, I-34014 Trieste, Italy; Univ Durham, Dept Phys, Durham DH1 3LE, England
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.