Work

Exact modeling of power spectrum multipole through spherical Fourier-Bessel basis

Year: 2024

Type: article

Abstract: The three-dimensional galaxy power spectrum is a powerful probe of primordial non-Gaussianity and additional general relativistic effects, which become important on large scales. At the same time, wide-angle (WA) effects due to differing lines-of-sight on the curved sky also become important with large angular separation. In this work, we accurately model WA and Doppler effects using the spherical Fourier-Bessel (SFB) formalism, before transforming the result into the commonly used power spectrum multipoles (PSM). This mapping from the SFB power spectrum to PSM represents a new way to nonperturbatively model WA and general relativistic effects present in the PSM, which we validate with log-normal mocks. Moreover, for the first time, we can compute the analytical PSM Gaussian covariance on large scales, exactly including WA-induced mode-couplings, without resorting to any plane-parallel approximations.

Source: Physical review. D/Physical review. D.

DOI: 10.1103/physrevd.110.083525

Authors: Robin Y. Wen, Henry S. Grasshorn Gebhardt, Chen Heinrich, Olivier Doré

Institutions: California Institute of Technology, Jet Propulsion Laboratory

Language: English

Topic: Cosmology and Gravitation Theories

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: National Aeronautics and Space Administration, California Institute of Technology, Jet Propulsion Laboratory, Goddard Space Flight Center

Awards: G2676722403, G3648211085, G830101876