Sign on

SAO/NASA ADS Astronomy Abstract Service


· Find Similar Abstracts (with default settings below)
· Electronic Refereed Journal Article (HTML)
· Full Refereed Journal Article (PDF/Postscript)
· arXiv e-print (arXiv:0908.1576)
· References in the article
· Citations to the Article (1) (Citation History)
· Refereed Citations to the Article
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
The late reionization of filaments
Authors:
Finlator, Kristian; Özel, Feryal; Davé, Romeel; Oppenheimer, Benjamin D.
Affiliation:
AA(Steward Observatory, The University of Arizona, Tucson, AZ, 85721, USA), AB(Steward Observatory, The University of Arizona, Tucson, AZ, 85721, USA), AC(Steward Observatory, The University of Arizona, Tucson, AZ, 85721, USA), AD(Leiden Observatory, Leiden University, Leiden, The Netherlands)
Publication:
Monthly Notices of the Royal Astronomical Society, Volume 400, Issue 2, pp. 1049-1061. (MNRAS Homepage)
Publication Date:
12/2009
Origin:
MNRAS
MNRAS Keywords:
radiative transfer , intergalactic medium , cosmology: theory , diffuse radiation , early Universe
Abstract Copyright:
(c) Journal compilation © 2009 RAS
DOI:
10.1111/j.1365-2966.2009.15521.x
Bibliographic Code:
2009MNRAS.400.1049F

Abstract

We study the topology of reionization using accurate three-dimensional radiative transfer calculations post-processed on outputs from cosmological hydrodynamic simulations. In our simulations, reionization begins in overdense regions and then `leaks' directly into voids, with filaments reionizing last owing to their combination of a high recombination rate and low emissivity. This result depends on the uniquely biased emissivity field predicted by our prescriptions for star formation and feedback, which have previously been shown to account for a wide array of measurements of the post-reionization Universe. It is qualitatively robust to our choice of simulation volume, ionizing escape fraction and spatial resolution (in fact, it grows stronger at higher spatial resolution) even though the exact overlap redshift is sensitive to each of these. However, it weakens slightly as the escape fraction is increased owing to the reduced density contrast at higher redshift. We also explore whether our results are sensitive to commonly employed approximations such as using optically thin Eddington tensors or substantially altering the speed of light. Such approximations do not qualitatively change the topology of reionization. However, they can systematically shift the overlap redshift by up to Δz ~ 0.5, indicating that accurate radiative transfer is essential for computing reionization. Our model cannot simultaneously reproduce the observed optical depth to Thomson scattering and ionization rate per hydrogen atom at z = 6, which could owe to numerical effects and/or missing early sources of ionization.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)

   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints