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arXiv · 1611.03590

Multitracer technique for galaxy bispectrum - An application to constraints on non-local primordial non-Gaussianities -

Daisuke Yamauchi·Shuichiro Yokoyama·Keitaro Takahashi
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Abstract

We explore the use of galaxy bispectra with multitracer technique as a possible probe of primordial non-Gaussianities. We forecast future constraints on non-linearity parameters, $f_{\rm NL}^{\rm eq}$ and $f_{\rm NL}^{\rm orth}$, which respectively characterize the equilateral- and orthogonal-types primordial bispectra, and show that the multitracer analysis would be effective with reducing the cosmic-variance noise if the number density of galaxies is high enough. We find that the measurement of galaxy bispectrum by future galaxy surveys can reach the constraints on the non-local type primordial non-Gaussianities to the level severer than current one which has been obtained by cosmic microwave background observations.

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Daisuke Yamauchi, Shuichiro Yokoyama, Keitaro Takahashi. 2016-11-11. Multitracer technique for galaxy bispectrum - An application to constraints on non-local primordial non-Gaussianities -. https://doi.org/10.1103/physrevd.95.063530

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