A new probe of the high-redshift Universe: nulling CMB lensing with interloper-free "LIM-pair" lensing
arXiv:2106.09005 · doi:10.1103/PhysRevD.105.083509
Abstract
Intermediate redshifts between galaxy surveys and the cosmic microwave background (CMB) remain unexplored territory. Line intensity mapping (LIM) offers a way to probe the Universe, including the epoch of reionization and the dark ages. Via exact nulling of the lensing kernel, we show that LIM lensing, in combination with galaxy (resp., CMB) lensing, can uniquely probe the (resp., pre-reionization) Universe. However, LIM foregrounds are a key hurdle to this futuristic technique. While continuum foregrounds can be controlled by discarding modes perpendicular to the line of sight (low modes), interloper foregrounds haven't been addressed in the context of LIM lensing. In this paper, we quantify the interloper bias to LIM lensing for the first time, and derive a ''LIM-pair'' estimator which avoids it exactly after cross-correlating with CMB lensing. This new quadratic lensing estimator works by combining two intensity maps in different lines, from the same redshift, whose interlopers are uncorrelated. As a result, this foreground avoidance method is robust to even large changes in the amplitude of the interloper power and non-Gaussianity. The cross-spectrum of the LIM-pair estimator with CMB lensing is thus robust to the currently large theoretical uncertainties in LIM modeling at high redshift.
arXiv commentSubmitted to PRL, comments welcome
References in corpus (48)
- Planck 2018 results. I. Overview and the cosmological legacy of Planck
- The Simons Observatory: Science goals and forecasts
- Weak Gravitational Lensing of the CMB
- Mass Reconstruction with CMB Polarization
- CMB-S4 Science Case, Reference Design, and Project Plan
- Planck 2013 results. XVII. Gravitational lensing by large-scale structure
- Multifrequency analysis of 21 cm fluctuations from the Era of Reionization
- Line-Intensity Mapping: 2017 Status Report
- Bias-Hardened CMB Lensing
- Measuring the 3D Clustering of Undetected Galaxies Through Cross Correlation of their Cumulative Flux Fluctuations from Multiple Spectral Lines
- Extragalactic Foreground Contamination in Temperature-based CMB Lens Reconstruction
- CMB Lensing Power Spectrum Biases from Galaxies and Clusters using High-angular Resolution Temperature Maps
- The Atacama Cosmology Telescope: A CMB lensing mass map over 2100 square degrees of sky and its cross-correlation with BOSS-CMASS galaxies
- Mitigating Foreground Biases in CMB Lensing Reconstruction Using Cleaned Gradients
- Intensity Mapping across Cosmic Times with the Lyman-Alpha Line
- Intensity mapping of [CII] from early galaxies
- On Removing Interloper Contamination from Intensity Mapping Power Spectrum Measurements
- Foreground-immune CMB lensing with shear-only reconstruction
- A wide field-of-view low-resolution spectrometer at APEX: instrument design and science forecast
- Lensing Reconstruction using redshifted 21cm Fluctuations
- Lower bias, lower noise CMB lensing with foreground-hardened estimators
- Spectral Line De-confusion in an Intensity Mapping Survey
- Quadratic estimators for CMB weak lensing
- A bias to CMB lensing measurements from the bispectrum of large-scale structure
- Foreground contamination in Ly-alpha intensity mapping during the epoch of reionization
- CMB lensing reconstruction biases in cross-correlation with large-scale structure probes
- Nulling Tomography with Weak Gravitational Lensing
- A Foreground Masking Strategy for [CII] Intensity Mapping Experiments Using Galaxies Selected by Stellar Mass and Redshift
- Bias to CMB Lensing Reconstruction from Temperature Anisotropies due to Large-Scale Galaxy Motions
- Multi-tracer intensity mapping: Cross-correlations, Line noise & Decorrelation
- Cosmic shear full nulling: sorting out dynamics, geometry and systematics
- Spherical Harmonic Analyses of Intensity Mapping Power Spectra
- Science Impacts of the SPHEREx All-Sky Optical to Near-Infrared Spectral Survey II: Report of a Community Workshop on the Scientific Synergies Between the SPHEREx Survey and Other Astronomy Observatories
- Game of cones: A nulling strategy for modelling lensing convergence in cones with large deviation theory
- Phase-Space Spectral Line De-confusion in Intensity Mapping
- Prospects for clustering and lensing measurements with forthcoming intensity mapping and optical surveys
- Lensing reconstruction from line intensity maps: the impact of gravitational nonlinearity
- Weak Lensing of Intensity Mapping: the Cosmic Infrared Background
- Astrophysics & Cosmology from Line Intensity Mapping vs Galaxy Surveys
- Cosmological constraints from line intensity mapping with interlopers
- Recovering lost 21 cm radial modes via cosmic tidal reconstruction
- Gravitational Lensing of Cosmological 21cm Emission
- Weak lensing with 21cm intensity mapping at
- First Detection of Cosmic Microwave Background Lensing and Lyman-α Forest Bispectrum
- Avoiding baryonic feedback effects on neutrino mass measurements from CMB lensing
- Bias to CMB lensing from lensed foregrounds
- Full-Sky Lensing Reconstruction of 21 cm Intensity Maps
- An excess of non-Gaussian fluctuations in the cosmic infrared background consistent with gravitational lensing
Cited by in corpus (11)
- Line-Intensity Mapping: Theory Review
- LIMFAST. II. Line Intensity Mapping as a Probe of High-Redshift Galaxy Formation
- Forecasts and Statistical Insights for Line Intensity Mapping Cross-Correlations: A Case Study with 21cm x [CII]
- Probing early structure and model-independent neutrino mass with high-redshift CMB lensing mass maps
- Cosmological Constraints on the Global Star Formation Law of Galaxies: Insights From Baryon Acoustic Oscillation Intensity Mapping
- A New Probe of the High-z BAO scale: BAO tomography With CMB LIM-Nulling Convergence
- Constraining Cosmology With the CMB LIM-Nulling Convergence
- Model independent variance cancellation in CMB lensing cross-correlations
- Removal of interloper contamination to line-intensity maps using correlations with ancillary tracers of the large-scale structure
- Cosmic shear nulling as a geometrical cosmological probe: Methodology and sensitivity to cosmological parameters and systematics
- CosmoGLINT: Cosmological Generative Model for Line Intensity Mapping with Transformer