As one main target of cosmological surveys, the galaxy peculiar velocity field encodes information about the cosmic structure growth history and significantly contributes to the study of dark energy and dark matter. Its detection is typically made by the redshift space distortion (RSD) and kinetic Sunyaev-Zel’dovich (kSZ) effects in cosmology. In this talk, I will present high signal-to-noise (>5) detections of the kSZ effect with different dataset combinations such as DESI+Planck or CMASS+ACT. As multi-tracers of the underlying velocity field, I will further highlight the applications of their synergy: on the cosmological side, adding kSZ effect helps breaking the degeneracy and improving the cosmological parameter constraints; on the astrophysical side, their synergy measures the halo electron density profile, which turns out to be an important diagnosis for studying the baryonic feedback effect during the galaxy evolution process. Finally, if I still have time, I will briefly introduce a new hybrid RSD model for the redshift space galaxy density power spectrum.
BIO
Yi Zheng graduated with a PhD from Shanghai Astronomical Observatory. After that, he worked as a postdoctoral researcher at the Korea Astronomy and Space Science Institute (KASI) and the Korea Institute for Advanced Study (KIAS) in Korea. He is now an associate professor in the School of Physics and Astronomy at Sun Yat-Sen University. His primary research field is the large-scale structure of the universe, with a particular interest on the peculiar velocity cosmology.
