2006/09/27 by J. Stuart B. Wyithe, Stuart Wyithe, Abraham Loeb +1 · 3 citations
Physics and Astronomy · #Astronomy #Astrophysics #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Intergalactic medium #Intergalactic travel #Luminosity #Luminous infrared galaxy #Physics #Radio Astronomy Observations and Technology #Radio galaxy #Redshift #Reionization #Superconducting and THz Device Technology #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2007.11366.x
10 pages, 6 figures. Submitted to MNRAS
arxiv created 2006/09/27 · openalex publication_date 2007/02/02 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Deep surveys have recently discovered galaxies at the tail end of the epoch of reionization. In the near future, these discoveries will be complemented by a new generation of low-frequency radio observatories that will map the distribution of neutral hydrogen in the intergalactic medium through its redshifted 21-cm emission. In this paper we calculate the expected cross-correlation between the distribution of galaxies and intergalactic 21-cm emission at high redshifts. We demonstrate using a simple model that overdense regions are expected to be ionized early as a result of their biased galaxy formation. This early phase leads to an anticorrelation between the 21-cm emission and the overdensities in galaxies, matter and neutral hydrogen. Existing Lyα surveys probe galaxies that are highly clustered in overdense regions. By comparing 21-cm emission from regions near observed galaxies to those away from observed galaxies, future observations will be able to test this generic prediction and calibrate the ionizing luminosity of high-redshift galaxies.