1610.00637
Imprint of DES super-structures on the Cosmic Microwave Background
Kovács, et al
Small temperature anisotropies in the CMB can be sourced by density perturbations via the late-time ISW effect. Large voids and superclusters are excellent environments to make a localized measurement of this tiny imprint. In some cases excess signals have been reported. Probe these claims with an independent data set, using the first year data of DES in a different footprint, and using a different super-structure finding strategy. Identified 52 large voids and 102 superclusters at 0.2<z<0.65. Use the Jubilee simulation to a priori evaluate the optimal ISW measurement configuration for the compensated top-hat filtering technique, and then perform a stacking measurement of the CMB temperature field based on the DES data. For optimal configurations, detect a cumulative cold imprint of voids with Delta T_f~ -5.0±3.7 uK and a hot imprint of superclusters Delta T_f~ 5.1±3.2 uK; this is ~1.2 sigma higher than the expected |DeltaT_f|~0.6 uK imprint of such super-structures in LCDM. If instead use an a posteriori selected filter size (R/Rv=0.6), can find a temperature decrement as large as Delta T_f~ -9.8±4.7 uK for voids, which is ~2sigma above LCDM expectations and is comparable to previous measurements made using SDSS super-structure data.
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