Cosmological evolution of heavy‐element and H2 abundances

  title={Cosmological evolution of heavy‐element and H2 abundances},
  author={Stephen J. Curran and John K Webb and Michael Murphy and Robert F Carswell},
  journal={Monthly Notices of the Royal Astronomical Society},
Spectroscopic observations of distant quasars have resulted in the detection of molecular hydrogen in intervening damped Lyman α absorption clouds (DLAs). We use observations compiled from different experimental groups to show that the molecular hydrogen abundance exhibits a dramatic increase over a cosmological time period corresponding to 13 to 24 per cent of the age of the Universe. We also tentatively show that the heavy-element abundances in the same gas clouds exhibit a faster and more… Expand

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