Impact & Mitigation of Polarized Extragalactic Foregrounds on Bayesian Cosmic Microwave Background Lensing

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Qu, Frank J., Millea, Marius, Schaan, Emmanuel
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912380264382464
author Qu, Frank J.
Millea, Marius
Schaan, Emmanuel
author_facet Qu, Frank J.
Millea, Marius
Schaan, Emmanuel
contents Future low-noise cosmic microwave background (CMB) lensing measurements from e.g., CMB-S4 will be polarization dominated, rather than temperature dominated. In this new regime, statistically optimal lensing reconstructions outperform the standard quadratic estimator, but their sensitivity to extragalactic polarized foregrounds has not been quantified. Using realistic simulations of polarized radio and infrared point sources, we show for the first time that optimal Bayesian lensing from a CMB-S4-like experiment is insensitive to the expected level of polarized extragalactic foregrounds after masking, as long as an accurate foreground power spectrum is included in the analysis. For more futuristic experiments where these foregrounds could cause a detectable bias, we propose a new method to jointly fit for lensing and the Poisson foregrounds, generalizing the bias hardening from the standard quadratic estimator to Bayesian lensing.
format Preprint
id arxiv_https___arxiv_org_abs_2406_15351
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Impact & Mitigation of Polarized Extragalactic Foregrounds on Bayesian Cosmic Microwave Background Lensing
Qu, Frank J.
Millea, Marius
Schaan, Emmanuel
Cosmology and Nongalactic Astrophysics
Future low-noise cosmic microwave background (CMB) lensing measurements from e.g., CMB-S4 will be polarization dominated, rather than temperature dominated. In this new regime, statistically optimal lensing reconstructions outperform the standard quadratic estimator, but their sensitivity to extragalactic polarized foregrounds has not been quantified. Using realistic simulations of polarized radio and infrared point sources, we show for the first time that optimal Bayesian lensing from a CMB-S4-like experiment is insensitive to the expected level of polarized extragalactic foregrounds after masking, as long as an accurate foreground power spectrum is included in the analysis. For more futuristic experiments where these foregrounds could cause a detectable bias, we propose a new method to jointly fit for lensing and the Poisson foregrounds, generalizing the bias hardening from the standard quadratic estimator to Bayesian lensing.
title Impact & Mitigation of Polarized Extragalactic Foregrounds on Bayesian Cosmic Microwave Background Lensing
topic Cosmology and Nongalactic Astrophysics
url https://arxiv.org/abs/2406.15351