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arXiv · 1611.04723

Large-scale tidal effect on redshift-space power spectrum in a finite-volume survey

Kazuyuki Akitsu·Masahiro Takada·Yin Li
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Abstract

Long-wavelength matter inhomogeneities contain cleaner information on the nature of primordial perturbations as well as the physics of the early universe. The large-scale coherent overdensity and tidal force, not directly observable for a finite-volume galaxy survey, are both related to the Hessian of large-scale gravitational potential and therefore of equal importance. We show that the coherent tidal force causes a homogeneous anisotropic distortion of the observed distribution of galaxies in all three directions, perpendicular and parallel to the line-of-sight direction. This effect mimics the redshift-space distortion signal of galaxy peculiar velocities, as well as a distortion by the Alcock-Paczynski effect. We quantify its impact on the redshift-space power spectrum to the leading order, and discuss its importance for the ongoing and upcoming galaxy surveys.

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Kazuyuki Akitsu, Masahiro Takada, Yin Li. 2016-11-15. Large-scale tidal effect on redshift-space power spectrum in a finite-volume survey. https://doi.org/10.1103/physrevd.95.083522

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