Multitracing Anisotropic Non-Gaussianity with Galaxy Shapes

Abstract

Correlations between intrinsic galaxy shapes on large-scales arise due to the effect of the tidal field of the large-scale structure. Anisotropic primordial non-Gaussianity induces a distinct scale-dependent imprint in these tidal alignments on large scales. Motivated by the observational finding that the alignment strength of luminous red galaxies depends on how galaxy shapes are measured, we study the use of two different shape estimators as a multi-tracer probe of intrinsic alignments. We show, by means of a Fisher analysis, that this technique promises a significant improvement on anisotropic non-Gaussianity constraints over a single-tracer method. For future weak lensing surveys, the uncertainty in the anisotropic non-Gaussianity parameter, $A_2$, is forecast to be $\sigma (A_2)\approx 50$, $\sim 40\%$ smaller than currently available constraints from the bispectrum of the Cosmic Microwave Background. This corresponds to an improvement of a factor of $4-5$ over the uncertainty from a single-tracer analysis.

11 pages, 4 figures, matches accepted version

References in corpus (9)

• 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
• Intrinsic galaxy alignments from the 2SLAQ and SDSS surveys: luminosity and redshift scalings and implications for weak lensing surveys
• Cosmological Collider Physics
• Constraints on intrinsic alignment contamination of weak lensing surveys using the MegaZ-LRG sample
• Intrinsic alignments of SDSS-III BOSS LOWZ sample galaxies
• Primordial non-Gaussianity: large-scale structure signature in the perturbative bias model
• Intrinsic alignments of galaxies in the MassiveBlack-II simulation: analysis of two-point statistics
• Controlling intrinsic alignments in weak lensing statistics: The nulling and boosting techniques

Cited by in corpus (8)

• Science with the space-based interferometer LISA. IV: Probing inflation with gravitational waves
• An EFT description of galaxy intrinsic alignments
• Scientific Synergy Between LSST and Euclid
• Scale-Dependent Galaxy Bias from Massive Particles with Spin during Inflation
• Primordial Non-Gaussianity
• Anisotropies of galaxy ellipticity correlations in real and redshift space: angular dependence in linear tidal alignment model
• Wide-angle effects on galaxy ellipticity correlations
• Galaxy clusters as intrinsic alignment tracers: present and future