Detection of extended He II reionization in the temperature evolution of the intergalactic medium

@article{Becker2010DetectionOE,
  title={Detection of extended He II reionization in the temperature evolution of the intergalactic medium},
  author={George D. Becker and James S. Bolton and Martin G. Haehnelt and W. Cambridge and Melbourne. and Caltech},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2010},
  volume={410},
  pages={1096-1112}
}
We present new measurements of the temperature of the intergalactic medium (IGM) derived from the Lyα forest over 2.0 ≤ z ≤ 4.8. The small-scale structure in the forest of 61 high-resolution quasi-stellar object spectra is quantified using a new statistic, the curvature, and the conversion to temperature calibrated using a suite of hydrodynamic simulations. At each redshift, we focus on obtaining the temperature at an optimal overdensity probed by the Lyα forest, T(Δ[overbar]), where the… 

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