Multi-tracing the primordial Universe with future surveys

Abstract

The fluctuations generated by Inflation are nearly Gaussian in the simplest models, but may be non-Gaussian in more complex models, potentially leading to signatures in the late Universe. In particular, local type primordial non-Gaussianity induces scale-dependent bias in tracers of the matter distribution. This non-Gaussian imprint in the tracer power spectrum survives at late times on ultra-large scales where nonlinearity is negligible. In order to combat the problem of growing cosmic variance on these scales, we use a multi-tracer analysis that combines different tracers to maximise any primordial signal. Previous work has investigated the combination of a spectroscopic galaxy survey with a 21cm intensity mapping survey in single-dish mode. We extend this work by considering instead the case where the 21cm intensity mapping survey is optimised for interferometer mode. As examples, we use two multi-tracer pairs of surveys: one at high redshift ($1\le z\le 2$) and one at very high redshift ($2\le z\le 5$). The 21cm surveys are idealised surveys based on HIRAX and PUMA. We implement foreground-avoidance filters and use detailed models of the interferometer thermal noise. The galaxy surveys are idealised surveys based on Euclid and MegaMapper. Via a simple Fisher forecast, we illustrate the potential of the multi-tracer. Our results show a $\sim 20-30\%$ improvement in precision on local primordial non-Gaussianity from the multi-tracer. Furthermore, we investigate the effects on constraints of varying the parameter of non-Gaussian galaxy assembly bias and of varying the parameters of the intensity mapping foreground filters. We find that the non-Gaussian galaxy assembly bias parameter causes a greater change in the constraints on local primordial non-Gaussianity than the foreground filter parameters.

15 pages, 8 figures. Minor improvements and corrections. Version accepted by EPJC

References in corpus (53)

• The Cosmic Linear Anisotropy Solving System (CLASS) II: Approximation schemes
• Stable clustering, the halo model and nonlinear cosmological power spectra
• The imprints of primordial non-gaussianities on large-scale structure: scale dependent bias and abundance of virialized objects
• Constraints on local primordial non-Gaussianity from large scale structure
• The effect of primordial non-Gaussianity on halo bias
• Measuring primordial non-gaussianity without cosmic variance
• What Next-Generation 21 cm Power Spectrum Measurements Can Teach Us About the Epoch of Reionization
• Late-time cosmology with 21cm intensity mapping experiments
• How to measure redshift-space distortions without sample variance
• Ingredients for 21cm intensity mapping
• Forecasting Cosmological Constraints from Redshift Surveys
• Ultra large-scale cosmology in next-generation experiments with single tracers
• Constraining Primordial non-Gaussianity with Bispectrum and Power Spectum from Upcoming Optical and Radio Surveys
• Constraining ultra large-scale cosmology with multiple tracers in optical and radio surveys
• Cosmological information in the redshift-space bispectrum
• Hunting down horizon-scale effects with multi-wavelength surveys
• Optimal Constraints on Local Primordial Non-Gaussianity from the Two-Point Statistics of Large-Scale Structure
• Why multi-tracer surveys beat cosmic variance
• Cosmological Measurements with General Relativistic Galaxy Correlations
• On the spatial distribution of neutral hydrogen in the Universe: bias and shot-noise of the HI Power Spectrum
• High-redshift post-reionization cosmology with 21cm intensity mapping
• SKAO HI Intensity Mapping: Blind Foreground Subtraction Challenge
• Can we actually constrain $f_{\mathrm{NL}}$ using the scale-dependent bias effect? An illustration of the impact of galaxy bias uncertainties using the BOSS DR12 galaxy power spectrum
• On the impact of galaxy bias uncertainties on primordial non-Gaussianity constraints
• Galaxy bias and primordial non-Gaussianity: insights from galaxy formation simulations with IllustrisTNG
• The Impact of Foregrounds on Redshift Space Distortion Measurements With the Highly-Redshifted 21 cm Line
• Reconstructing large-scale structure with neutral hydrogen surveys
• Constraining primordial non-Gaussianity using two galaxy surveys and CMB lensing
• Forecasts on Primordial non-Gaussianity from 21 cm Intensity Mapping experiments
• Magnification and evolution biases in large-scale structure surveys
• The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: a multi-tracer analysis in Fourier space for measuring the cosmic structure growth and expansion rate
• Information content in the redshift-space galaxy power spectrum and bispectrum
• Primordial non-Gaussianity from the Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey I: Catalogue Preparation and Systematic Mitigation
• Calibrating photometric redshifts with intensity mapping observations
• Detecting the relativistic galaxy bispectrum
• The foreground transfer function for HI intensity mapping signal reconstruction: MeerKLASS and precision cosmology applications
• Detecting the relativistic bispectrum in 21cm intensity maps
• The degeneracy between primordial non-Gaussianity and foregrounds in 21cm intensity mapping experiments
• Linear bias forecasts for emission line cosmological surveys
• Non-Gaussianity Constraints using Future Radio Continuum Surveys and the Multi-Tracer Technique
• Wide-angle and relativistic effects in Fourier-space clustering statistics
• Deconvolving the Wedge: Maximum-Likelihood Power Spectra via Spherical-Wave Visibility Modeling
• The HI intensity mapping bispectrum including observational effects
• Multi-tracer power spectra and bispectra: Formalism
• Constraining primordial non-Gaussianity by combining next-generation galaxy and 21 cm intensity mapping surveys
• Constraints on the growth rate using the observed galaxy power spectrum
• Constraining the growth rate by combining multiple future surveys
• Multi-wavelength spectroscopic probes: biases from neglecting light-cone effects
• The local PNG bias of neutral Hydrogen, ${\mathrm{H}}_{\mathrm{I}}$
• Validating the Fisher approach for stage IV spectroscopic surveys
• Wide-angle effects in multi-tracer power spectra with Doppler corrections
• Cosmological Fisher forecasts for next-generation spectroscopic surveys
• Radio-optical synergies at high redshift to constrain primordial non-Gaussianity

Cited by in corpus (3)

• PNG-UNITsims: Halo clustering response to primordial non-Gaussianities as a function of mass
• Primordial non-Gaussianity -- the effects of relativistic and wide-angle corrections to the power spectrum
• Constraining primordial non-Gaussianity by combining photometric galaxy and 21cm intensity mapping surveys