About Me
Education: I am currently a PhD student in cosmology at the University of Edinburgh, supervised by John Peacock. Previously, I obtained MMathPhys at the University of Oxford.
Research Interests: I am interested in how large scale structures in the universe were formed. I study this using large galaxy surveys, via galaxy clustering, redshift space distortion, cross-correlation of large scale structures with the CMB, CMB lensing, the Intgrated Sachs-Wolfe effect, and cosmic super voids.
Publications: ADS link
Research
The imprints of galaxy clustering in the DESI Legacy Survey on the CMB
The trajectory of CMB photons are perturbed by the gravitational potentials of LSS according to General Relativity. This leaves imprints of the LSS on the CMB sky. I used the public DESI Legacy Survey data to measure cross-correlations between galaxy tomography and the CMB lensing and temperature map. You can find more about it on the paper here. There is a short summary poster here.
GAMA: 2D cross-correlation between galaxies and groups
The GAMA (Galaxy And Mass Assembly) survey is a spectroscopic survey with high completeness, and therefore an ideal survey to study galaxy groups out to redshift 0.3. In this project, I measured the 2D correlation function of groups split by stellar mass and galaxies split by colour. The anisotropy in the correlation function is referred to as the Redshift Space Distortion, which is related to the galaxy peculiar velocities with respect to the group centre. This is used to study different galaxy and group biases, as well as the growth rate of the large scale structures. You can find the draft paper here. A short summary poster can be found here.
The stacked ISW signal from supervoids
There have been many claims in the literature that there is excess ISW signal from super-voids. The ISW effect arises from perturbation of the CMB photon energy from LSS, and is a direct result of dark energy domination. To test the robustness of the signal, I repeat such analysis on the DESI Legacy Survey, which has a large sky coverage. This is an ongoing project.
Contact
Email: qhang@roe.ac.uk
Address: Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh, UK, EH9 3HJ