Beyond the traditional Line-of-Sight approach of cosmological angular statistics

Abstract

We present a new efficient method to compute the angular power spectra of large-scale structure observables that circumvents the numerical integration over Bessel functions, expanding on a recently proposed algorithm based on FFTlog. This new approach has better convergence properties. The method is explicitly implemented in the CLASS code for the case of number count $C_{\ell }$'s (including redshift-space distortions, weak lensing, and all other relativistic corrections) and cosmic shear $C_{\ell }$'s. In both cases our approach speeds up the calculation of the exact $C_{\ell }$'s (without the Limber approximation) by a factor of order 400 at a fixed precision target of 0.1%.

arXiv comment40 pages, 6 figures; v2: one reference added

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Cited by in corpus (28)

• Non-linear perturbation theory extension of the Boltzmann code CLASS
• Beyond Limber: Efficient computation of angular power spectra for galaxy clustering and weak lensing
• 2D-FFTLog: Efficient computation of real space covariance matrices for galaxy clustering and weak lensing
• The observed galaxy power spectrum in General Relativity
• Beware of commonly used approximations I: errors in forecasts
• The Full-Sky Angular Bispectrum in Redshift Space
• CosmicNet II: Emulating extended cosmologies with efficient and accurate neural networks
• Precise and Accurate Cosmology with CMBxLSS Power Spectra and Bispectra
• CosmicNet I: Physics-driven implementation of neural networks within Boltzmann-Einstein solvers
• Neutrino mass bounds from confronting an effective model with BOSS Lyman-alpha data
• Nonlinear Redshift-Space Distortions in the Harmonic-space Galaxy Power Spectrum
• Constraints on the growth rate using the observed galaxy power spectrum
• Constraining the growth rate by combining multiple future surveys
• Cosmological Angular Trispectra and Non-Gaussian Covariance
• Generalisation of the Kaiser Rocket effect in general relativity in the wide-angle galaxy 2-point correlation function
• Modelling the next-to-leading order matter three-point correlation function using FFTLog
• On the asymptotic connection between full- and flat-sky angular correlators
• Constraining low redshift [CII] Emission by Cross-Correlating FIRAS and BOSS Data
• Weak Lensing Trispectrum and Kurt-Spectra
• Flat-sky Angular Power Spectra Revisited
• Multi-Messenger Astrophysics with the Cosmic Neutrino Background
• Linear Relativistic Corrections in the Spherical Fourier-Bessel Power Spectrum
• Projected two- and three-point statistics: Forecasts and mitigation of non-linear RSDs
• Cross-correlating radial peculiar velocities and CMB lensing convergence
• Speeding up the detectability of the harmonic-space galaxy bispectrum
• Data-driven Cosmology from Three-dimensional Light Cones
• pylevin: Efficient numerical integration of integrals containing up to three Bessel functions
• Comments on the mass sheet degeneracy in cosmography analyses