Scientific Seminars
The dark mark of large-scale structure on the Cosmic Microwave Background
Ben Granett
INAF-OABrera
2010-11-24 14:00 Brera - Cupola Fiore
New techniques in data-mining cosmic microwave background observations reveal the signatures of structure growth and dark energy. I will present work on the integrated Sachs-Wolfe (ISW) effect, a direct measure of the growth of structure and cosmic acceleration. We isolate the ISW signal by identifying large-scale over and under-densities in the matter distribution and measuring their effect on CMB photons. We find imprints on the CMB of order 10muK which is in agreement with the predictions from Gaussian fluctuations in a LCDM Universe. I will also discuss the observational evidence for the Dark Flow discovered by Kashlinsky et al from the kinetic Sunyaev-Zeldovich effect and also observed in galaxy peculiar velocities. We detect the dipole signal at low significance in the cluster-WMAP CMB cross power spectrum providing additional support that it arises from the intracluster gas. |