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arXiv · 1704.03405

Can anisotropy in the galaxy distribution tell the bias?

Biswajit Pandey
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Abstract

We use information entropy to analyze the anisotropy in the mock galaxy catalogues from dark matter distribution and simulated biased galaxy distributions from $\Lambda$CDM N-body simulation. We show that one can recover the linear bias parameter of the simulated galaxy distributions by comparing the radial, polar and azimuthal anisotropies in the simulated galaxy distributions with that from the dark matter distribution. This method for determination of the linear bias requires only $O(N)$ operations as compared to $O(N^{2})$ or at least $O(N \log N)$ operations required for the methods based on the two-point correlation function and the power spectrum. We apply this method to determine the linear bias parameter for the galaxies in the 2MASS Redshift Survey (2MRS) and find that the 2MRS galaxies in the $K_{s}$ band have a linear bias of $\sim 1.3$.

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Biswajit Pandey. 2017-04-11. Can anisotropy in the galaxy distribution tell the bias?. https://doi.org/10.1093/mnras%2Fstx912

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