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arXiv · 1808.08044

Hunting for Statistical Anisotropy in Tensor Modes with B-mode Observations

Takashi Hiramatsu·Shuichiro Yokoyama·Tomohiro Fujita·Ippei Obata
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Abstract

We investigate a possibility of constraining statistical anisotropies of the primordial tensor perturbations by using future observations for the Cosmic Microwave Background (CMB) B-mode polarization. By parameterizing a statistically-anisotropic tensor power spectrum as $P_h ({\boldsymbol{k}}) = P_h (k) \sum_n g_n \cos^n θ_{\boldsymbol{k}}$, where $θ_{\boldsymbol{k}}$ is an angle of the direction of $\hat{k}={\boldsymbol{k}}/k$ from a preferred direction, we find that it would be possible for future B-mode observations such as CMB-S4 to detect the tensor statistical anisotropy at the level of $g_n \sim {\mathcal O} (0.1)$.

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Takashi Hiramatsu, Shuichiro Yokoyama, Tomohiro Fujita, Ippei Obata. 2018-08-24. Hunting for Statistical Anisotropy in Tensor Modes with B-mode Observations. https://doi.org/10.1103/physrevd.98.083522

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