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/

Global: Zendy Plus annual

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

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We measure the skewness power spectrum of the Cosmic Microwave Background(CMB) anisotropies optimized for a detection of the secondary bispectrumgenerated by the correlation of the CMB lensing potential with integratedSachs-Wolfe effect and the Sunyaev-Zel'dovich effect. The covariance of ourmeasurements is generated by Monte-Carlo simulations of Gaussian CMB fieldswith noise properties consistent with Wilkinson Microwave Anisotropy Probe(WMAP) 5-year data. When interpreting multi-frequency measurements we also takeinto account the confusion resulting from unresolved radio point sources. Weanalyze Q, V and W-band WMAP 5-year raw and foreground-cleaned maps using theKQ75 mask out to l_max=600. We find no significant evidence for a non-zeronon-Gaussian signal from the lensing-secondary correlation in all three bandsand we constrain the overall amplitude of the cross power spectrum between CMBlensing potential and the sum of SZ and ISW fluctuations to be 0.42 \pm 0.86and 1.19 \pm 0.86 in combined V and W-band raw and foreground-cleaned mapsprovided by the WMAP team, respectively. The point source amplitude at thebispectrum level measured with this skewness power spectrum is higher thanprevious measurements of point source non-Gaussianity. We also consider ananalysis where we also account for the primordial non-Gaussianity in additionto lensing-secondary bispectrum and point sources. The focus of this paper ison secondary anisotropies. Consequently the estimator is not optimised forprimordial non-Gaussianity and the limit we find on local non-Gaussianity fromthe foreground-cleaned V+W maps is f_NL = -13 \pm 62, when marginalized overpoint sources and lensing-ISW/SZ constributions to the total bispectrum.

Non-Gaussianity in WMAP Data Due to the Correlation of CMB Lensing Potential with Secondary Anisotropies