Speaker
Description
Axions are hypothetical elementary particles with their small masses and tiny couplings to matter sectors, and they are known as the promising candidates for the dark matter in our Universe. Axions generically couple to the photon via the chiral anomaly effect and differentiate the phase velocities between two circularly-polarized photons, which leads to a rotation of photon's polarization plane called the birefringence effect. Interestingly, if the axion behaves as dark matter, the induced birefringence angle slightly oscillates in time with a frequency of axion mass, which is quite advantageous to extract the signal from the foreground in the real-time measurements of cosmological/astrophysical sources. In this talk, I will present a recent development of axion dark matter search with the observations of such a cosmic birefringence effect.
