Hao-Ran Yu (于浩然)

KIAA-CITA Joint Postdoctoral Fellow
Room: 
218
Research interests: 
Cosmology, large scale structure of the universe, N-body simulations
haoran tiannu
Research Highlights: 

In 2015, we ran the world's largest N-body simualtion TianNu on world's fastest Tianhe-2 supercomputer. The simulation coevolves cold dark matter (CDM) and neutrinos by using total of 3 trillion particles, and models normal hierachy of neutrino with mass 0.05 eV. From the simulation we discovered the differential neutrino condensation effect. 

The above fiugre shows a 2D visualization of TianNu at redshift z = 0.01, in terms of column density of CDM and neutrinos in a projection of full-size, but an 8.3 Mpc/h slice of the simulation. As shown in the right-hand-side two colorbars for CDM and neutrinos respectively, the blue-white and orange show respectively CDM and neutrino high column density regions. In the main figure one can see that the bright blue filaments show the CDM large scale structure of the Universe whereas more diffused orange "clouds" trace those filaments on a larger scale. The bottom right two panels zoom in two 35 Mpc/h regions from the main figure. They have similar CDM structure, however the upper structure is surrounding a dense cluster on its right hand side (see in the main figure), as a result it is called "neutrino-rich" compared to the other "neutrino-poor" region. Our result shows that halo (galaxy) properties are different in these two regions.

Original Nature article: https://www.nature.com/articles/s41550-017-0143

Other TianNu related works can be found in my research.

Main Involvements: 

I am a joint postdoctoral fellow at the KIAA and the Canadian Institute for Theoretical Astrophysics.