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Title: The mildly non-linear regime of structure formation

Journal Article · · Journal of Cosmology and Astroparticle Physics
 [1];  [2]
  1. Center for Astrophysics, Harvard University, 60 Garden St., Cambridge, MA 02138 (United States)
  2. School of Natural Sciences, Institute for Advanced Study, Olden Lane, Princeton, NJ 08540 (United States)

We present a simple physically motivated picture for the mildly non-linear regime of structure formation, which captures the effects of the bulk flows. We apply this picture to develop a method to significantly reduce the sample variance in cosmological N-body simulations at the scales relevant to the Baryon Acoustic Oscillations (BAO). The results presented in this paper will allow for a speed-up of an order of magnitude (or more) in the scanning of the cosmological parameter space using N-body simulations for studies which require a good handle of the mildly non-linear regime, such as those targeting the BAO. Using this physical picture we develop a simple formula, which allows for the rapid calculation of the mildly non-linear matter power spectrum to percent level accuracy, and for robust estimation of the BAO scale.

OSTI ID:
22280113
Journal Information:
Journal of Cosmology and Astroparticle Physics, Vol. 2012, Issue 04; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
Country of Publication:
United States
Language:
English