Improved Forecasts for the Baryon Acoustic Oscillations and Cosmological Distance Scale

• Published in: The Astrophysical journal Vol. 665; no. 1; pp. 14 - 24
• Main Authors: Seo, Hee-Jong, Eisenstein, Daniel J
• Format: Journal Article
• Language: English
• Published: Chicago, IL IOP Publishing 10.08.2007; University of Chicago Press
• Subjects: Astronomy; Earth, ocean, space; Exact sciences and technology; Cosmological parameter; Cosmic background radiation; Distance scale; cosmic microwave background; Cosmology; Large-scale structure; large-scale structure of universe; Baryons; cosmological parameters
• ISSN: 0004-637X; 1538-4357
• DOI: 10.1086/519549

We present the cosmological distance errors achievable using the baryonic acoustic oscillations as a standard ruler. We begin from a Fisher matrix formalism that is upgraded from earlier Seo and Elsenstein work. We isolate the information from the baryonic peaks by excluding distance information from other less robust sources. Meanwhile, we accommodate the Lagrangian displacement distribution into the Fisher matrix calculation to reflect the gradual loss of information in scale and in time due to nonlinear growth, nonlinear bias, and nonlinear redshift distortions. We then show that we can contract the multidimensional Fisher matrix calculations into a two-dimensional or even one-dimensional formalism with physically motivated approximations. We present the resulting fitting formula for the cosmological distance errors from galaxy redshift surveys as a function of survey parameters and nonlinearity, which saves us going through the 12 dimensional Fisher matrix calculations. Finally, we show excellent agreement between the distance error estimates from the revised Fisher matrix and the precision on the distance scale recovered from N-body simulations.