Transitioning from Stage-III to Stage-IV: Cosmology from galaxy$\times$CMB lensing and shear$\times$CMB lensing

Abstract

We examine the cosmological constraining power from two cross-correlation probes between galaxy and CMB surveys: the cross-correlation of lens galaxy density with CMB lensing convergence $⟨\delta \kappa ⟩$, and source galaxy weak lensing shear with CMB lensing convergence $⟨\gamma \kappa ⟩$. These two cross-correlation probes provide an independent cross-check of other large-scale structure constraints and are insensitive to galaxy-only or CMB-only systematic effects. In addition, when combined with other large-scale structure probes, the cross-correlations can break degeneracies in cosmological and nuisance parameters, improving both the precision and robustness of the analysis. In this work, we study how the constraining power of $⟨\delta \kappa ⟩+⟨\gamma \kappa ⟩$ changes from Stage-III (ongoing) to Stage-IV (future) surveys. Given the flexibility in selecting the lens galaxy sample, we also explore systematically the impact on cosmological constraints when we vary the redshift range and magnitude limit of the lens galaxies using mock galaxy catalogs. We find that in our setup, the contribution to cosmological constraints from $⟨\delta \kappa ⟩$ and $⟨\gamma \kappa ⟩$ are comparable in the Stage-III datasets; but in Stage-IV surveys, the noise in $⟨\delta \kappa ⟩$ becomes subdominant to cosmic variance, preventing $⟨\delta \kappa ⟩$ to further improve the constraints. This implies that to maximize the cosmological constraints from future $⟨\delta \kappa ⟩+⟨\gamma \kappa ⟩$ analyses, we should focus more on the requirements on $⟨\gamma \kappa ⟩$ instead of $⟨\delta \kappa ⟩$. Furthermore, the selection of the lens sample should be optimized in terms of our ability to characterize its redshift or galaxy bias instead of its number density.

18 pages, 13 figures

References in corpus (14)

• Dark Energy Survey Year 3 Results: Cosmological Constraints from Galaxy Clustering and Weak Lensing
• Dark energy constraints from cosmic shear power spectra: impact of intrinsic alignments on photometric redshift requirements
• Dark Energy Survey Year 3 Results: Cosmology from Cosmic Shear and Robustness to Data Calibration
• Dark Energy Survey Year 3 Results: Cosmology from Cosmic Shear and Robustness to Modeling Uncertainty
• Dark Energy Survey Year 1 Results: Multi-Probe Methodology and Simulated Likelihood Analyses
• Cosmological constraints from unWISE and Planck CMB lensing tomography
• $Euclid$ preparation: XV. Forecasting cosmological constraints for the $Euclid$ and CMB joint analysis
• Dark Energy Survey Year 3 Results: Optimizing the Lens Sample in Combined Galaxy Clustering and Galaxy-Galaxy Lensing Analysis
• Scale Dependent Galaxy Bias in the SDSS as a function of Luminosity and Colour
• Dark Energy Survey Year 3 Results: Multi-Probe Modeling Strategy and Validation
• Precise and Accurate Cosmology with CMBxLSS Power Spectra and Bispectra
• Cosmology from Clustering, Cosmic Shear, CMB Lensing, and Cross Correlations: Combining Rubin Observatory and Simons Observatory
• Validating Synthetic Galaxy Catalogs for Dark Energy Science in the LSST Era
• The Physical Origin of Dark Energy Constraints from Rubin Observatory and CMB-S4 Lensing Tomography

Cited by in corpus (8)

• DEMNUni: The imprint of massive neutrinos on the cross-correlation between cosmic voids and CMB lensing
• Future prospects on testing extensions to $\Lambda$CDM through the weak lensing of gravitational waves
• LiteBIRD Science Goals and Forecasts: A full-sky measurement of gravitational lensing of the CMB
• Forecasting the power of Higher Order Weak Lensing Statistics with automatically differentiable simulations
• Skewing the CMB$\times$LSS: a Fast Method for Bispectrum Analysis
• The catalog-to-cosmology framework for weak lensing and galaxy clustering for LSST
• Improving Photometric Galaxy Clustering Constraints With Cross-Bin Correlations
• The Hydrostatic Mass Bias and the ${\sigma }_8$ Tension: A Multi-Probe Forecast for Stage-IV/V Surveys