The Cosmic Microwave Background is the relic of radiation from the period of recombination (when electrons first bound to protons) around 300,000 years after the Big Bang. This radiation is extremely uniform in all directions with minute fluctuations caused by the gravitational collapse of structure in the early Universe as seen in the famous CMB fluctuation maps. However, this signal is only revealed once the movement of our own Galaxy (around 600km/s) is correctly accounted for. This motion causes a dominant dipole signal to be superimposed upon the CMB map. It is assumed that all of the measured dipole is due to the motion of the Milky Way. This assumption can be tested by large area surveys (greater than half the sky) which are sensitive to large numbers of sources (many times greater than a million). This project will investigate whether the approximate one billion objects in NASA’s all-sjy mid-infrared WISE survey can measure this dipole using novel selection criteria. This project will also confirm the previous results from large area surveys and estimate the strength of this signal from upcoming radio surveys.
Dr Guillaume Drouart
Research Associate (Formerly)Read More