The 21 Centimeter Forest: Radio Absorption Spectra as Probes of Minihalos before Reionization
View/ Open
Author
Furlanetto, Steven R.
Loeb, Abraham
Published Version
https://doi.org/10.1086/342757Metadata
Show full item recordCitation
Furlanetto, Steven R., and Abraham Loeb. 2002. “The 21 Centimeter Forest: Radio Absorption Spectra as Probes of Minihalos before Reionization.” The Astrophysical Journal 579 (1): 1–9. https://doi.org/10.1086/342757.Abstract
We study the absorption along lines of sight toward high-z radio sources caused by the 21 cm transition of neutral hydrogen in the intergalactic medium (IGM) before reionization. Using semianalytic methods, we compute the number density of observable features caused by both "minihalos" ( bound objects that are unable to cool efficiently because of their small virial temperatures) and protogalactic disks. We show that both sets of features should be observable by the next generation of low-frequency radio telescopes, including the Low Frequency Array and the Square Kilometer Array, provided that sufficiently bright background sources exist. The statistics of minihalo absorption features seen along lines of sight to radio-loud quasars offer a way to measure the evolution of the radiation background and the IGM temperature with cosmic time. Intersections with disks are much less common but cause significantly deeper absorption features that would be visible in the spectra of both radio-loud quasars and gamma-ray bursts (GRBs). The absorption feature caused by H I in the host galaxy of a GRB should be observable, offering a route to determine spectroscopically the burst redshift.Terms of Use
This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAACitable link to this page
http://nrs.harvard.edu/urn-3:HUL.InstRepos:41393329
Collections
- FAS Scholarly Articles [18276]
Contact administrator regarding this item (to report mistakes or request changes)