Testing the WMAP cosmology via Planck radio catalogues
  The prime evidence underpinning the standard LCDM cosmological model is the
CMB power spectrum as observed by WMAP and other microwave experiments. But
Sawangwit & Shanks (2010) have recently shown that the WMAP CMB power spectrum
is highly sensitive to the beam profile of the WMAP telescope. Here, we use the
source catalogue from the Planck Early Data Release to test further the WMAP
beam profiles. We confirm that stacked beam profiles at Q, V and particularly
at W appear wider than expected when compared to the Jupiter beam, normalised
either directly to the radio source profiles or using Planck fluxes. The same
result is also found based on WMAP-CMBfree source catalogues and NVSS sources.
The accuracy of our beam profile measurements is supported by analysis of CMB
sky simulations. However the beam profiles from WMAP7 at the W band are
narrower than previously found in WMAP5 data and the rejection of the WMAP beam
is now only at the ~3sigma level. We also find that the WMAP source fluxes
demonstrate possible non-linearity with Planck fluxes. But including
ground-based and Planck data for the bright Weiland et al (2011) sources may
suggest that the discrepancy is a linear offset rather than a non-linearity.
Additionally, we find that the stacked Sunyaev-Zel'dovich (SZ) decrements of
~151 galaxy clusters observed by Planck are in agreement with the WMAP data. We
find that there is no evidence for a WMAP SZ deficit as has previously been
reported. In the particular case of Coma we find evidence for the presence of
an ~0.1mK downwards CMB fluctuation. We conclude that beam profile systematics
can have significant effects on both the amplitude and position of the acoustic
peaks, with potentially important implications for cosmology parameter fitting.
