"Thomas Smid" writes:

Shortly after the first release of the WMAP data three years ago, I
made already the point that the angular power spectrum of the CMB
fluctuations is at least partly due to a systematic error (see my
webpage http://www.physicsmyths.org.uk/wmap.htm ).

As noted on a separate thread on sci.astro by Greg Henessy and myself,
the claims you make on that page are erroneous. Briefly,
* you assign "Poissonian" uncertainties to the data when the
limiting uncertainties are not Poissonian (Jarosik et al 2003
(statistics); Bennet et al 2003 (foregrounds));
* you fundamentally misinterpret estimated uncertainties as *biases*
when they are not (your Fig. 5 shows subtraction of uncertainties,
which is not a relevant quantity);
* you assume that the authors don't account for the WMAP
instrumental beam pattern, when in fact they do (Hinshaw et al
2003);
* you make other erroneous assumptions about how the angular power
spectrum is made; despite having been referred to the Hinshaw
paper several times, you apparently have not read it.

Thus, based on shaky premises, your conclusions are highly suspect.

This is in my opinion now confirmed by the latest data release:
the difference between the 3- and 1-year maps shows residuals that have
about the same amplitude as the second peak near 0.3 degree in the
power spectrum. This is evident from Figs.3 and 9 in
http://map.gsfc.nasa.gov/m_mm/pub_pa...p_3yr_temp.pdf
(PDF file, 2.3 MB) which reveals a residual temperature fluctuation for
the difference map of about =20microK.
[ note corrected value ]

And do you have evidence that these differences appear at the relevant
angular frequencies? Since the maximum differences appear near the
galactic plane, and much smaller differences appear on very broad
spatial scales (i.e. low l), the answer would probably be, "no."

... Considering the circumstance
that the difference map was smoothed with a 1 degree radius (which
should have about halved the amplitude) this corresponds thus to the
amplitude of the second peak (which is 50microK). The latter proves
therefore to be due due to statistical fluctuations both in space and
time which, as shown on my webpage, lead to an angular bias resulting
in a residual signal at about 0.3 deg.

Unlikely (see above).

Also, your "Update April 2006" section does not account for several
factors. First, while the exposure *per observation* is a small
amount (as perhaps the 77 msec that you quote), the WMAP analysis
involves averaging many observations together. Thus, the standard
error of the mean will be much smaller than the value you quote for
the statistical error for one measurement. Even if your estimated
statistical uncertainty had been correct, it is a statistical
uncertainty and *not* a bias, and so neighboring angular frequency
bins would not be correlated, as the real data are.

CM

References
C.L. Bennett, et al., 2003, ApJS, 148, 97
G. Hinshaw, et al., 2003, ApJS, 148, 135
N. Jarosik, et al., 2003, ApJS, 148, 29