English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

The Cosmic Microwave Background (CMB) radiation B mode polarization signalcontains the unique signature of primordial metric perturbations producedduring the inflation. The separation of the weak CMB B-mode signal from strongforeground contamination in observed maps is a complex task, and proposed newgeneration low noise satellite missions compete with the weak signal level ofthis gravitational background. In this article, for the first time, we employ aforeground model-independent internal linear combination (ILC) method toreconstruct the CMB B mode signal using simulated observations over largeangular scales of the sky of 6 frequency bands of future generation CMB missionProbe of Inflation and Cosmic Origins (PICO). We estimate the joint CMB B modeposterior density following the interleaving Gibbs steps of B mode angularpower spectrum and cleaned map samples using the ILC method. We extend andimprove the earlier reported Bayesian ILC method to analyze weak CMB B modereconstruction by introducing noise bias corrections at two stages during theILC weight estimation. By performing $200$ Monte Carlo simulations of theBayesian ILC method, we find that our method can reconstruct the CMB signalsand the joint posterior density accurately over large angular scales of thesky. We estimate Blackwell-Rao statistics of the marginal density of CMB B modeangular power spectrum and use them to estimate the joint density of scalar totensor ratio $r$ and a lensing power spectrum amplitude $A^{\textrm{lens}}$.Using $200$ Monte Carlo simulations of the delensing approach, we find that ourmethod can achieve an unbiased detection of the primordial gravitational wavesignal $r$ with more than 8$\sigma$ significance for levels of $r \geqslant0.01$.

A Bayesian ILC method for CMB B-mode posterior estimation and reconstruction of primordial gravity wave signal