2004/09/07 by Nissim Kanekar, N. Kanekar, F. H. Briggs
Physics and Astronomy · #Absorption (acoustics) #Absorption spectroscopy #Astronomy #Astrophysics #Astrophysics and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #Galaxy #Optics #Physics #Radio Astronomy Observations and Technology #Redshift #Spectroscopy #astro-ph
paper · pdf · doi:10.1016/j.newar.2004.09.030
published as New Astron.Rev. 48 (2004) 1259-1270 · 12 pages, 7 figures. Uses espcrc2.sty. To appear in "Science with the Square Kilometer Array," eds. C. Carilli and S. Rawlings, New Astronomy Reviews (Elsevier: Amsterdam)
arxiv created 2004/09/07 · openalex publication_date 2004/11/12 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
HI 21~cm absorption spectroscopy provides an excellent probe of the neutral gas content of absorbing galaxies, yielding information on their kinematics, mass, physical size and ISM conditions. The high sensitivity, unrivaled frequency coverage and RFI suppression techniques of the SKA will enable it to use HI absorption to study the ISM of high column density intervening systems along thousands of lines of sight out to high redshifts. Blind SKA 21~cm surveys will yield large, unbiased absorber samples, tracing the evolution of normal galaxies and active galactic nuclei from z \gtrsim 6 to the present epoch. It will thus be possible to directly measure the physical size and mass of typical galaxies as a function of redshift and, hence, to test hierarchical models of structure formation.