A photoionization instability in the early intergalactic medium
Article Abstract:
Instability in the pre-galactic medium on scales of more than a photon path in length can be attributed to any roughly uniform source of ionizing photons. This photoionization-induced instability causes regions of low density to become even less dense since they get less ionizing energy per atom. The resulting changes in density can initiate the forming of protogalaxies and intergalactic clouds, removing the requirement for gas clouds or density variations with other causes that earlier models of galaxy formation had invoked.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
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A characteristic size of ~10 Mpc for the ionized bubbles at the end of cosmic reionization
Article Abstract:
Combined constraints of cosmic variance and light travel time imply an observed bubble size at the end of the overlap epoch of ~10 physical Mpc, and a scatter in the observed redshift of overlap along different lines-of-sight of ~0.15. This scatter is consistent with observational constraints from spectroscopic data on the farthest known quasars.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2004
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Cosmic upsilon-ray background from structure formation in the intergalactic medium
Article Abstract:
New research into the shock waves caused by gravity in the gas of the intergalatic medium is presented.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2000
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