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Cold gas, the HI 21cm line and evolving galactic potentials

F. H. Briggs
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Abstract

Neutral hydrogen traces gravitational potentials. In the nearby universe, 21cm emission-line surveys show that the bulk of the HI resides in well-formed, optically-luminous galaxies. At high redshift, 21cm line absorption against background radio quasars occurs in gas-rich systems identified with the highest HI column densities -- the ``damped Lyman alpha'' quasar absorption-line systems. High spatial-resolution observations of the redshifted 21cm line absorbers measure sizes and kinematics of the neutral absorbers.

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F. H. Briggs. 2000-01-05. Cold gas, the HI 21cm line and evolving galactic potentials. https://arxiv.org/abs/astro-ph/0001070

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