Quantitative Constraints on the Reionization History from the IGM Damping Wing Signature in Two Quasars at z > 7

  title={Quantitative Constraints on the Reionization History from the IGM Damping Wing Signature in Two Quasars at z > 7},
  author={Frederick B. Davies and Joseph F. Hennawi and Eduardo Ba{\~n}ados and Zarija Luki'c and Roberto Decarli and Xiaohui Fan and Emanuele Paolo Farina and Chiara Mazzucchelli and Hans-Walter Rix and Bram P. Venemans and Fabian Walter and Feige Wang and Jinyi Yang},
  journal={arXiv: Cosmology and Nongalactic Astrophysics},
During reionization, neutral hydrogen in the intergalactic medium (IGM) imprints a damping wing absorption feature on the spectrum of high-redshift quasars. A detection of this signature provides compelling evidence for a significantly neutral Universe, and enables measurements of the hydrogen neutral fraction $x_{\rm HI}(z)$ at that epoch. Obtaining reliable quantitative constraints from this technique, however, is challenging due to stochasticity induced by the patchy inside-out topology of… Expand
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