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arXiv · 2409.12004

First confirmation of anisotropic halo bias from statistically anisotropic matter distributions

Shogo Masaki·Maresuke Shiraishi·Takahiro Nishimichi·Teppei Okumura·Shuichiro Yokoyama
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Abstract

We confirm for the first time the existence of distinctive halo bias associated with the quadrupolar type of statistical anisotropy (SA) of the linear matter density field using cosmological $N$-body simulations. We find that the coefficient of the SA-induced bias for cluster-sized halos takes negative values and exhibits a decreasing trend with increasing halo mass. This results in the quadrupole halo power spectra in a statistically anisotropic universe being less amplified compared to the monopole spectra. The anisotropic feature in halo bias that we found presents a promising new tool for testing the hypothesis of a statistically anisotropic universe, with significant implications for the precise verification of anisotropic inflation scenarios and vector dark matter and dark energy models.

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Shogo Masaki, Maresuke Shiraishi, Takahiro Nishimichi, Teppei Okumura, Shuichiro Yokoyama. 2024-09-18. First confirmation of anisotropic halo bias from statistically anisotropic matter distributions. https://arxiv.org/abs/2409.12004

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