The primordial information content of Rayleigh Anisotropies

Abstract

Anisotropies in the cosmic microwave background (CMB) are primarily generated by Thomson scattering of photons by free electrons. Around recombination, the Thomson scattering probability quickly diminishes as the free electrons combine with protons to form neutral hydrogen off which CMB photons can scatter through Rayleigh scattering. Unlike Thomson scattering, Rayleigh scattering is frequency dependent resulting in the generation of anisotropies with a different spectral dependence. Unfortunately the Rayleigh scattering efficiency rapidly decreases with the expansion of the neutral universe, with the result that only a small percentage of photons are scattered by neutral hydrogen. Although the effect is very small, future CMB missions with higher sensitivity and improved frequency coverage are poised to measure Rayleigh scattering signal. The uncorrelated component of the Rayleigh anisotropies contains unique information on the primordial perturbations that could potentially be leveraged to expand our knowledge of the early universe. In this paper we explore whether measurements of Rayleigh scattering anisotropies can be used to constrain primordial non-Gaussianity (NG) and examine the hints of anomalies found by WMAP and \textit{Planck} satellites. We show that the additional Rayleigh information has the potential to improve primordial NG constraints by $30\%$, or more. Primordial bispectra that are not of the local type benefit the most from these additional scatterings, which we attribute to the different scale dependence of the Rayleigh anisotropies. Unfortunately this different scaling means that Rayleigh measurements can not be used to constrain anomalies or features on large scales. On the other hand, anomalies that may persist to smaller scales, such as the potential power asymmetry seen in WMAP and \textit{Planck}, could be improved by the addition of Rayleigh measurements.

arXiv comment12 pages, 5 figures

References in corpus (76)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• Efficient Computation of CMB anisotropies in closed FRW models
• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Preliminary Maps and Basic Results
• Cosmological parameters from CMB and other data: a Monte-Carlo approach
• Non-Gaussian features of primordial fluctuations in single field inflationary models
• Planck 2018 results. X. Constraints on inflation
• A Line of Sight Approach to Cosmic Microwave Background Anisotropies
• The Simons Observatory: Science goals and forecasts
• Acoustic Signatures in the Primary Microwave Background Bispectrum
• The imprints of primordial non-gaussianities on large-scale structure: scale dependent bias and abundance of virialized objects
• Asymmetries in the CMB anisotropy field
• Single field consistency relation for the 3-point function
• Primordial Non-Gaussianities from Inflation Models
• A high resolution foreground cleaned CMB map from WMAP
• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Are There Cosmic Microwave Background Anomalies?
• Planck 2013 results. XXIII. Isotropy and statistics of the CMB
• Detection of non-Gaussianity in the WMAP 1-year data using spherical wavelets
• Planck 2018 results. VII. Isotropy and Statistics of the CMB
• BICEP2 / Keck Array x: Constraints on Primordial Gravitational Waves using Planck, WMAP, and New BICEP2/Keck Observations through the 2015 Season
• Planck 2018 results. IV. Diffuse component separation
• Non-Gaussianities in Single Field Inflation and their Optimal Limits from the WMAP 5-year Data
• Limits on non-Gaussianities from WMAP data
• Measuring primordial non-gaussianity without cosmic variance
• Large Non-Gaussianities in Single Field Inflation
• Large Nongaussianity in Axion Inflation
• A Per-Baseline, Delay-Spectrum Technique for Accessing the 21cm Cosmic Reionization Signature
• Cosmological Tests of Gravity
• The Epoch of Reionization Window: I. Mathematical Formalism
• Planck 2015 results. IX. Diffuse component separation: CMB maps
• Measuring primordial non-Gaussianity in the cosmic microwave background
• How to measure redshift-space distortions without sample variance
• Gravitational lensing as a contaminant of the gravity wave signal in CMB
• Signatures of Initial State Modifications on Bispectrum Statistics
• The Observed Squeezed Limit of Cosmological Three-Point Functions
• The Epoch of Reionization Window: II. Statistical Methods for Foreground Wedge Reduction
• Foregrounds for observations of the cosmological 21 cm line: I. First Westerbork measurements of Galactic emission at 150 MHz in a low latitude field
• Delensing CMB Polarization with External Datasets
• Power Asymmetry in Cosmic Microwave Background Fluctuations from Full Sky to Sub-degree Scales: Is the Universe Isotropic?
• General CMB and Primordial Bispectrum Estimation I: Mode Expansion, Map-Making and Measures of f_NL
• The Clustering of Galaxies in SDSS-III DR9 Baryon Oscillation Spectroscopic Survey: Constraints on Primordial Non-Gaussianity
• Primordial Bispectrum Information from CMB Polarization
• The LiteBIRD Satellite Mission - Sub-Kelvin Instrument
• Constraining Primordial non-Gaussianity with Bispectrum and Power Spectum from Upcoming Optical and Radio Surveys
• Non-Gaussianity from Step Features in the Inflationary Potential
• Parameter constraints from cross-correlation of CMB lensing with galaxy clustering
• An Improved Method for 21cm Foreground Removal
• Is the Universe odd?
• Optimal Estimation of Non-Gaussianity
• The Pesky Power Asymmetry
• Constraining local non-Gaussianities with kSZ tomography
• Lack of large-angle TT correlations persists in WMAP and Planck
• CMB Delensing Beyond the B Modes
• Demonstration of cosmic microwave background delensing using the cosmic infrared background
• A low CMB variance in the WMAP data
• CMB Observations and the Production of Chemical Elements at the End of the Dark Ages
• Forecasts on Primordial non-Gaussianity from 21 cm Intensity Mapping experiments
• Crinkles in the last scattering surface: Non-Gaussianity from inhomogeneous recombination
• The full squeezed CMB bispectrum from inflation
• Bayesian inflationary reconstructions from Planck 2018 data
• Capturing Non-Gaussianity of the Large-Scale Structure with Weighted Skew-Spectra
• PICO: Probe of Inflation and Cosmic Origins
• Tensor Non-Gaussianity Search: Current Status and Future Prospects
• Non-Gaussianities from Perturbing Recombination
• Bayesian inference of CMB gravitational lensing
• Rayleigh Scattering and Microwave Background Fluctuations
• On the non-Gaussianity from Recombination
• Rayleigh scattering: blue sky thinking for future CMB observations
• A map-based method for eliminating systematic modes from galaxy clustering power spectra with application to BOSS
• Minimizing gravitational lensing contributions to the primordial bispectrum covariance
• The Effects of Rayleigh Scattering on the CMB and Cosmic Structure
• Cosmic Visions Dark Energy: Science
• The Effects of Bandpass Variations on Foreground Removal Forecasts for Future CMB Experiments
• The Imprint of Lithium Recombination on the Microwave Background Anisotropies
• Probing higher-spin fields from inflation with higher-order statistics of the CMB
• Packed Ultra-wideband Mapping Array (PUMA): Astro2020 RFI Response
• Requirements for future CMB satellite missions: photometric and band-pass response calibration

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• CCAT-prime Collaboration: Science Goals and Forecasts with Prime-Cam on the Fred Young Submillimeter Telescope
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