%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 }