Interpreting map-based E/B spectral properties of CMB foregrounds

Clicks: 2
ID: 322799
2026
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Emerging

Ranked #794 of 913 articles by views in monthly notices of the royal astronomical society

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 913 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
Abstract Map-space E/B decompositions of linear polarization are attractive for foreground and CMB analyses because they separate parity families: B-family patterns directly contaminate primordial tensor searches, while E-family patterns trace coherent Galactic structures. However, the E/B transform is not fully local and can induce apparent spectral complexity even when the underlying sky is spectrally simple in $\underline{P}=Q+iU$. We quantify this effect for synchrotron emission using complex log–Taylor and moment expansions for $\underline{P}$, its spin-preserving projections $\underline{P}_E$ and $\underline{P}_B$, and its more standard scalar projections E and B. We relate the coefficients of these expansions to physical mechanisms such as line-of-sight mixing, synchrotron ageing, and Faraday effects. Using simple sky models, we show how $\underline{P}_E$ and $\underline{P}_B$ reorganize the spectral behaviour of $\underline{P}$ into parity families with a clear geometric meaning. They retain interpretable amplitudes and angles and satisfy the closure relation $\underline{P}=\underline{P}_E+\underline{P}_B$, which extends to all moment orders. By contrast, scalar quantities such as |E| and |B| show larger induced variability of effective spectral parameters and enhanced spectral complexity, while E + iB lacks interpretable polarization amplitude and angle. Finally, we present simple CMB-oriented applications: three-frequency diagnostics to test whether the sky is better described by a power law in P or by separate effective laws in (PE, PB), and idealized ILC and masking examples showing that the preferred map-space field depends on where foreground simplicity and residual contamination reside. This framework provides practical diagnostics for choosing foreground modelling, cleaning, and masking strategies in Galactic and CMB B-mode analyses.
Reference Key
openalex_W7171553343 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors G. Weymann-Despres, L. Vacher, Michael E. Jones, A. Taylor, C. Baccigalupi, A J Banday, R D P Grumitt, Nicoletta Krachmalnicoff
Journal monthly notices of the royal astronomical society
Year 2026
DOI
10.1093/mnras/stag1432
URL
https://doi.org/10.1093/mnras/stag1432
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.