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Speaker	Cover, Keith S
Talk Title	Recallibration of the WMAP CMB data shows no anisotropies is a better fit
Abstract	The purpose of this reanalysis of the WMAP uncalibrated time ordered data (TOD) was two fold. The first was to assess the reliability of the algorithm used to reconstruct the official WMAP sky maps of the CMB from the TOD. In particular, to investigate the possibility that some part of the reported anisotropies might be an artefact of the image reconstruction used due to calibration issues. The second was to evaluate a proposed criterion for ensuring reliable detection of a signal of interest. The proposed criterion was that, for the reliable detection of a signal of interest, it must be demonstrated that all images consistent with the data have the signal of interest. The proposed criterion was implemented by testing the null hypothesis that the TOD was consistent with no anisotropies when WMAP's hourly calibration parameters were allowed to vary. It was shown independently for all 20 WMAP channels that sky maps with no anisotropies outside the galactic band, other than the dipole, were a better fit to the uncalibrated TOD than those from the official analysis. Thus the official WMAP analysis does not satisfy the proposed criterion raising the possibility that the reported anisotropies are artefacts of the image reconstruction. The recently launched Planck satellite, because of its use of repetitive circular scans, will be the first instrument able to detect the reported anisotropies without the use of image reconstruction. Thus Planck will provide an independent check of both the image reconstruction used in the WMAP official analysis and the proposed criterion. Assuming the proposed criterion is correct, the results of this reanalysis suggest that if Planck detects any anisotropies they will be many times smaller than those reported by WMAP.
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