Large fluctuations in the hydrogen-ionizing background and mean free
path following the epoch of reionization
F. Davies, and S. Furlanetto. (2015)cite arxiv:1509.07131Comment: 13 pages, 11 figures, submitted to MNRAS.
Abstract
Extremely large opaque troughs in the Lyman-alpha forest have been
interpreted as a sign of an extended reionization process below z~6. Such
features are impossible to reproduce with simple models of the intergalactic
ionizing background that assume a uniform mean free path of ionizing photons.
We build a self-consistent model of the ionizing background that includes
fluctuations in the mean free path due to the varying strength of the ionizing
background and large-scale density field. The dominant effect is the
suppression of the ionizing background in large-scale voids due to
"self-shielding" by an enhanced number of optically thick absorbers. Our model
results in a distribution of 50 Mpc/h Lyman-alpha forest effective optical
depths that significantly improves agreement with the observations at z~5.6.
Extrapolation to z~5.4 and z~5.8 appears promising, but matching the mean
background evolution requires evolution in the absorber population beyond the
scope of the present model. We also demonstrate the need for extremely large
volumes (>400 Mpc on a side) to accurately determine the incidence of rare
large-scale features in the Lyman-alpha forest.
Description
[1509.07131] Large fluctuations in the hydrogen-ionizing background and mean free path following the epoch of reionization
%0 Generic
%1 davies2015large
%A Davies, Frederick B.
%A Furlanetto, Steven R.
%D 2015
%K free function high-z hydrogen mean path
%T Large fluctuations in the hydrogen-ionizing background and mean free
path following the epoch of reionization
%U http://arxiv.org/abs/1509.07131
%X Extremely large opaque troughs in the Lyman-alpha forest have been
interpreted as a sign of an extended reionization process below z~6. Such
features are impossible to reproduce with simple models of the intergalactic
ionizing background that assume a uniform mean free path of ionizing photons.
We build a self-consistent model of the ionizing background that includes
fluctuations in the mean free path due to the varying strength of the ionizing
background and large-scale density field. The dominant effect is the
suppression of the ionizing background in large-scale voids due to
"self-shielding" by an enhanced number of optically thick absorbers. Our model
results in a distribution of 50 Mpc/h Lyman-alpha forest effective optical
depths that significantly improves agreement with the observations at z~5.6.
Extrapolation to z~5.4 and z~5.8 appears promising, but matching the mean
background evolution requires evolution in the absorber population beyond the
scope of the present model. We also demonstrate the need for extremely large
volumes (>400 Mpc on a side) to accurately determine the incidence of rare
large-scale features in the Lyman-alpha forest.
@misc{davies2015large,
abstract = {Extremely large opaque troughs in the Lyman-alpha forest have been
interpreted as a sign of an extended reionization process below z~6. Such
features are impossible to reproduce with simple models of the intergalactic
ionizing background that assume a uniform mean free path of ionizing photons.
We build a self-consistent model of the ionizing background that includes
fluctuations in the mean free path due to the varying strength of the ionizing
background and large-scale density field. The dominant effect is the
suppression of the ionizing background in large-scale voids due to
"self-shielding" by an enhanced number of optically thick absorbers. Our model
results in a distribution of 50 Mpc/h Lyman-alpha forest effective optical
depths that significantly improves agreement with the observations at z~5.6.
Extrapolation to z~5.4 and z~5.8 appears promising, but matching the mean
background evolution requires evolution in the absorber population beyond the
scope of the present model. We also demonstrate the need for extremely large
volumes (>400 Mpc on a side) to accurately determine the incidence of rare
large-scale features in the Lyman-alpha forest.},
added-at = {2015-09-25T09:48:54.000+0200},
author = {Davies, Frederick B. and Furlanetto, Steven R.},
biburl = {https://www.bibsonomy.org/bibtex/22522797d64526fc8e2f1e76b95eed167/miki},
description = {[1509.07131] Large fluctuations in the hydrogen-ionizing background and mean free path following the epoch of reionization},
interhash = {bbceac3851ce91cd442f7fe5a445c078},
intrahash = {2522797d64526fc8e2f1e76b95eed167},
keywords = {free function high-z hydrogen mean path},
note = {cite arxiv:1509.07131Comment: 13 pages, 11 figures, submitted to MNRAS},
timestamp = {2015-09-25T09:48:54.000+0200},
title = {Large fluctuations in the hydrogen-ionizing background and mean free
path following the epoch of reionization},
url = {http://arxiv.org/abs/1509.07131},
year = 2015
}