Open AccessGalaxy surveys, inhomogeneous re‐ionization and dark energy
Author(s) -
Pritchard Jonathan R.,
Furlanetto Steven R.,
Kamionkowski Marc
Publication year - 2007
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2006.11131.x
Subject(s) - physics , astrophysics , dark energy , galaxy , redshift , ionization , ansatz , astronomy , cosmology , quantum mechanics , ion
ABSTRACT We examine the effect of inhomogeneous re‐ionization on the galaxy power spectrum and the consequences for probing dark energy. To model feedback during re‐ionization, we apply an ansatz setting the galaxy overdensity proportional to the underlying ionization field. Thus, inhomogeneous re‐ionization may leave an imprint in the galaxy power spectrum. We evolve this imprint to low redshift and use the Fisher‐matrix formalism to assess the effect on parameter estimation. We show that a combination of low‐redshift ( z = 0.3) and high‐redshift ( z = 3) galaxy surveys can constrain the size of cosmological H ii regions during re‐ionization. This imprint can also cause confusion when using baryon oscillations or other features of the galaxy power spectrum to probe the dark energy. We show that when bubbles are large, and hence detectable, our ability to constrain w can be degraded by up to 50 per cent. When bubbles are small, the imprint has little or no effect on measuring dark energy parameters.