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arXiv · astro-ph/9912091

Non-Voigt Lyman-alpha absorption line profiles

P. J. Outram·R. F. Carswell·T. Theuns
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Abstract

Recent numerical simulations have lead to a paradigm shift in our understanding of the intergalactic medium, and the loss of a physical justification for Voigt profile fitting of the Lyman-alpha forest. Many individual lines seen in simulated spectra have significant departures from the Voigt profile, yet could be well fitted by a blend of two or more such lines. We discuss the expected effect on the line profiles due to ongoing gravitational structure formation and Hubble expansion. We develop a method to detect departures from Voigt profiles of the absorption lines in a statistical way and apply this method to simulated Lyman-alpha forest spectra, confirming that the profiles seen do statistically differ from Voigt profiles.

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P. J. Outram, R. F. Carswell, T. Theuns. 1999-12-06. Non-Voigt Lyman-alpha absorption line profiles. https://doi.org/10.1086/312468

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