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arXiv · 1606.03092

Consistency of the growth rate in different environments with the 6dF Galaxy Survey: measurement of the void-galaxy and galaxy-galaxy correlation functions

Ixandra Achitouv·Chris Blake·Paul Carter·Jun Koda·Florian Beutler
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Abstract

We present a new test of gravitational physics by comparing the growth rate of cosmic structure measured around voids with that measured around galaxies in the same large-scale structure dataset, the low-redshift 6-degree Field Galaxy Survey. By fitting a self-consistent Redshift Space Distortion model to the 2D galaxy-galaxy and void-galaxy correlation functions, we recover growth rate values f\sigma_8 = 0.42 \pm 0.06 and 0.39 \pm 0.11, respectively. The environmental-dependence of cosmological statistics can potentially discriminate between modified-gravity scenarios which modulate the growth rate as a function of scale or environment and test the underlying assumptions of homogeneity and isotropy.

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Ixandra Achitouv, Chris Blake, Paul Carter, Jun Koda, Florian Beutler. 2016-06-09. Consistency of the growth rate in different environments with the 6dF Galaxy Survey: measurement of the void-galaxy and galaxy-galaxy correlation functions. https://doi.org/10.1103/physrevd.95.083502

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