Year: 2022
Type: article
Abstract: The effects of gravitational lensing of the cosmic microwave background (CMB) have been measured at high significance with existing data and will be measured even more precisely in future surveys. Reversing the effects of lensing on the observed CMB temperature and polarization maps provides a variety of benefits. Delensed CMB spectra have sharper acoustic peaks and more prominent damping tails, allowing for improved inferences of cosmological parameters that impact those features. Delensing reduces B-mode power, aiding the search for primordial gravitational waves and allowing for lower variance reconstruction of lensing and other sources of secondary CMB anisotropies. Lensing-induced power spectrum covariances are reduced by delensing, simplifying analyses and improving constraints on primordial non-Gaussianities. Biases that result from incorrectly modeling nonlinear and baryonic feedback effects on the lensing power spectrum are mitigated by delensing. All of these benefits are possible without any changes to experimental or survey design. We develop a self-consistent, iterative, all-orders treatment of CMB delensing on the curved sky and demonstrate the impact that delensing will have with future surveys.
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Awards: G130463927, LIGHT RELICS OF THE EARLY UNIVERSE, G2229954460, G2432923657, RESEARCH AT THE ENERGY FRONTIER AT SOUTHERN METHODIST UNIVERSITY, RESEARCH IN THEORETICAL/EXPERIMENTAL HIGH ENERGY PHYSICS (TASK T-1, T-2 AND P), Programs on Critical Problems in Physics, Astrophysics and Biophysics at the Aspen Center for Physics
OpenAlex ID: W3215914026