Poster Presentation

Cross-correlation of WISE galaxies and Planck temperature sky maps

Dani C.Y. Chao(NTHU), Tomotsugu Goto(NTHU)

The Integrated Sachs-Wolfe effect promises a way to study Dark Energy: Dark Energy causes the decay of gravitational potential wells while photons passing through, thus the red-shifting of photons can not compensate the blue-shifting of them, which results in a correlation between hotspots in the CMB temperature anisotropies and the overdensities. The LambdaCDM model predicts that the correlation is tiny, 3% of the primordial CMB temperature fluctuations. In this ISW cross-correlation analysis, we use a sample of galaxies from the Wide-field Infrared Survey Explorer (WISE) with CMB temperature data from the latest Planck data release. We provide a better method to select galaxies from the WISE survey to measure the correlation of the overdensities and the CMB temperature anisotropies. Previous studies had discrepancy between their measurements and the prediction from LambdaCDM model. With our enhanced sample of galaxies, we show a result with a higher significance.