Imprint of anisotropic primordial non-Gaussianity on halo intrinsic alignments in simulations
Kazuyuki Akitsu, Toshiki Kurita, Takahiro Nishimichi, Masahiro Takada, Satoshi Tanaka
Abstract
Using $N$-body simulations of cosmological large-scale structure formation, for the first time, we show that the anisotropic primordial non-Gaussianity 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 primordial non-Gaussianity coefficient ${f}_{\mathrm{NL}}^{s=2}$ at a precision comparable with or better than that of the cosmic microwave background.