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arXiv · 2007.03670

Imprint of anisotropic primordial non-Gaussianity on halo intrinsic alignments in simulations

Kazuyuki Akitsu·Toshiki Kurita·Takahiro Nishimichi·Masahiro Takada·Satoshi Tanaka
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Abstract

Using $N$-body simulations of cosmological large-scale structure formation, for the first time, we show that the anisotropic primordial non-Gaussianity (PNG) causes a scale-dependent modification, given by $1/k^2$ at small $k$ limit, in the three-dimensional power spectra of halo shapes (intrinsic alignments), whilst the conventional power spectrum of halo number density field remains unaffected. We discuss that wide-area imaging and spectrocopic surveys observing the same region of the sky allow us to constrain the quadrupole PNG coefficient $f_{\rm NL}^{s=2}$ at a precision comparable with or better than that of the cosmic microwave background.

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Kazuyuki Akitsu, Toshiki Kurita, Takahiro Nishimichi, Masahiro Takada, Satoshi Tanaka. 2020-07-07. Imprint of anisotropic primordial non-Gaussianity on halo intrinsic alignments in simulations. https://doi.org/10.1103/physrevd.103.083508

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