[astro-ph/0604358] Galaxy surveys, inhomogeneous reionization, and dark energy

Authors:  Jonathan R. Pritchard (1), Steven R. Furlanetto (2), Marc Kamionkowski (1) ((1) Caltech, (2) Yale)
Abstract:  We examine the effect of inhomogeneous reionization on the galaxy power spectrum and the consequences for probing dark energy. To model feedback during reionization, we apply an ansatz setting the galaxy overdensity proportional to the underlying ionization field. Thus, inhomogeneous reionization 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- (z=0.3) and high- (z=3) redshift galaxy surveys can constrain the size of cosmological HII regions during reionization. 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%. When bubbles are small, the imprint has little or no effect on measuring dark-energy parameters.
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Sarah Bridle
Posts: 144
Joined: September 24 2004
Affiliation: University College London (UCL)

[astro-ph/0604358] Galaxy surveys, inhomogeneous reionizatio

Post by Sarah Bridle » April 19 2006

Very interesting.
Would be interested to see the neutrino mass included in the parameter analysis.
Since there is a bit of degeneracy with ns then maybe there is significant degeneracy with neutrino mass?

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