Article

On the presence of thermal Sunyaev-Zel'dovich induced signal in the first-year WMAP temperature maps

Monthly Notices of the Royal Astronomical Society (Impact Factor: 5.52). 01/2004; 347(2):403-410. DOI: 10.1111/j.1365-2966.2004.07205.x
Source: arXiv

ABSTRACT Using available optical and X-ray catalogues of clusters and
superclusters of galaxies, we build templates of thermal
Sunyaev-Zel'dovich (tSZ) emission as they should be detected by the WMAP
experiment. We compute the cross-correlation of our templates with WMAP
temperature maps, and interpret our results separately for clusters and
for superclusters of galaxies. For clusters of galaxies, we claim
2-5σ detections in our templates built from the BCS (Ebeling et
al.), NORAS (Böhringer et al.) and de Grandi et al. catalogues. In
these templates, the typical cluster temperature decrements in WMAP maps
are around 15-35 μK in the Rayleigh-Jeans range (no beam
deconvolution applied). Several tests probing the possible influence of
foregrounds in our analyses demonstrate that our results are robust
against Galactic contamination. On supercluster scales, we detect a
diffuse component in the V and W WMAP bands, which cannot be generated
by superclusters in our catalogues (Einasto et al.), and which is not
present in the clean map of Tegmark et al. Using this clean map, our
analyses yield, for Einasto's supercluster catalogues, the following
upper limit for the Comptonization parameter associated with
supercluster scales: ySC < 2.18 × 10-8 at
the 95 per cent confidence level.

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