The mean free path of ionizing photons at 5 < z < 6: evidence for rapid evolution near reionization

  title={The mean free path of ionizing photons at 5 < z < 6: evidence for rapid evolution near reionization},
  author={George D. Becker and Anson D’Aloisio and Holly M. Christenson and Yong Zhu and G{\'a}bor Worseck and James S Bolton},
  journal={Monthly Notices of the Royal Astronomical Society},
The mean free path of ionizing photons, λmfp, is a key factor in the photoionization of the intergalactic medium (IGM). At z ≳ 5, however, λmfp may be short enough that measurements towards QSOs are biased by the QSO proximity effect. We present new direct measurements of λmfp that address this bias and extend up to z ∼ 6 for the first time. Our measurements at z ∼ 5 are based on data from the Giant Gemini GMOS survey and new Keck LRIS observations of low-luminosity QSOs. At z ∼ 6 we use QSO… Expand
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