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arXiv · 0907.0735

Probing the Epoch of Reionization with the Lyman Alpha Forest at z~4-5

Renyue Cen·Patrick McDonald·Hy Trac·Abraham Loeb
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Abstract

The inhomogeneous cosmological reionization process leaves tangible imprints in the intergalactic medium down to z=4-5. The Lyman-alpha forest flux power spectrum provides a potentially powerful probe of the epoch of reionization. With the existing SDSS I/II quasar sample we show that two cosmological reionization scenarios, one completing reionization at z=6 and the other at z=9, can be distinguished at ~7 sigma level by utilizing Lyman alpha forest absorption spectra at z=4.5+-0.5, in the absence of other physical processes that may also affect the Lyman alpha flux power spectrum. The redshift range z=4-5 may provide the best window, because there is still enough transmitted flux and quasars to measure precise statistics of the flux fluctuations, and the IGM still retains a significant amount of memory of reionization.

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Renyue Cen, Patrick McDonald, Hy Trac, Abraham Loeb. 2009-07-04. Probing the Epoch of Reionization with the Lyman Alpha Forest at z~4-5. https://doi.org/10.1088/0004-637x/706/1/l164

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