Precision Cosmology with Cosmic Voids

par Dr Alice Pisani (CPPM (Marseille) and IAP (Paris))

lundi 13 avr. 2015, 14:00 → 15:00 Europe/Paris

Amphithéâtre (CPPM)

Modern surveys allow us to access to high quality measurements, by sampling the galaxy distribution in detail also in the emptier regions, voids. Cosmic voids present themselves as a new tool to constrain cosmology. While the treatment of systematics is simpler in these empty regions, with the aim of achieving the level of precision cosmology a careful modeling of such effects is necessary. In particular, peculiar velocities affect the way we observe cosmic voids, and thus their effect needs to be understood. Using mock catalogues, I analyse the effect of peculiar velocities on void properties. In this talk, I first describe the algorithm to find voids in galaxy surveys. I then present the results of the analysis of the systematic effects affecting voids and discuss it in the framework of current and future surveys. Additionally, I present a preliminary forecast for void abundances with the future Euclid and Wfirst missions and obtain, using the Fisher matrix formalism, a prediction for the constraints that void abundances will set on cosmological parameters.

Slides AlicePisaniCPPMSeminar2015.pdf