T. Biesiadzinski, J. J. McMahon, C. J. Miller, B. Nord, L. Shaw
One of the central goals of multi-wavelength galaxy cluster cosmology is to
unite all cluster observables to form a consistent understanding of cluster
mass. Here, we study the impact of systematic effects from optical cluster
catalogs on stacked SZ signals. We show that the optically predicted
Y-decrement can vary by as much as 50% based on the current 2 sigma systematic
uncertainties in the observed mass-richness relationship. Mis-centering and
impurities will suppress the SZ signal compared to expectations for a clean and
perfectly centered optical sample, but to a lesser degree. We show that the
level of these variations and suppression is dependent on the amount of
systematics in the optical cluster catalogs. We also study luminosity-dependent
sub-sampling of the optical catalog, which creates Malmquist-like effects that
biases upwards the observed Y-decrement of the stacked signal. We show that the
current Planck measurements of the Y-decrement around SDSS optical clusters and
their X-ray counterparts are consistent with expectations after accounting for
the 1sigma (2sigma) optical systematic uncertainties using the Johnston (Rozo)
mass-richness relation.
View original:
http://arxiv.org/abs/1201.1282
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