Constraining the intergalactic medium at z ≈ 9.1 using LOFAR Epoch of Reionization observations

  title={Constraining the intergalactic medium at z ≈ 9.1 using LOFAR Epoch of Reionization observations},
  author={Raghunath Ghara and Sambit K. Giri and Garrelt Mellema and Benedetta Ciardi and Saleem Zaroubi and Ilian T Iliev and L. V. E. Koopmans and Emma Chapman and Simon Gazagnes and B K Gehlot and A. Ghosh and V. Jelic and F G Mertens and Rajesh Mondal and Joop Schaye and M. B. Silva and K. M. B. Asad and Robin Kooistra and Maaijke Mevius and Andr{\'e} R. Offringa and Vishambhar N. Pandey and Sarod Yatawatta},
  journal={Monthly Notices of the Royal Astronomical Society},
We derive constraints on the thermal and ionization states of the intergalactic medium (IGM) at redshift ≈ 9.1 using new upper limits on the 21-cm power spectrum measured by the LOFAR radio telescope and a prior on the ionized fraction at that redshift estimated from recent cosmic microwave background (CMB) observations. We have used results from the reionization simulation code GRIZZLY and a Bayesian inference framework to constrain the parameters which describe the physical state of the IGM… Expand
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