Disantangling the effects of Doppler velocity and primordial non-Gaussianity in galaxy power spectra

Abstract

We study the detectability of large-scale velocity effects on galaxy clustering, by simulating galaxy surveys and combining the clustering of different types of tracers of large-scale structure. We employ a set of lognormal mocks that simulate a $20.000$ deg${}^2$ near-complete survey up to $z=0.8$, in which each galaxy mock traces the spatial distribution of dark matter of that mock with a realistic bias prescription. We find that the ratios of the monopoles of the power spectra of different types of tracers carry most of the information that can be extracted from a multi-tracer analysis. In particular, we show that with a multi-tracer technique it will be possible to detect velocity effects with $\gtrsim 3\sigma$. Finally, we investigate the degeneracy of these effects with the (local) non-Gaussianity parameter $f_{\mathrm{NL}}$, and how large-scale velocity contributions could be mistaken for the signatures of primordial non-Gaussianity.

17 pages, 25 figures

References in corpus (7)

• The imprints of primordial non-gaussianities on large-scale structure: scale dependent bias and abundance of virialized objects
• Measuring primordial non-gaussianity without cosmic variance
• New Perspective on Galaxy Clustering as a Cosmological Probe: General Relativistic Effects
• Primordial non-Gaussianity: large-scale structure signature in the perturbative bias model
• Einstein's legacy in galaxy surveys
• Probing primordial non-Gaussianity via iSW measurements with SKA continuum surveys
• Probing the primordial Universe with MeerKAT and DES

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