The Voids-within-Voids-within-Voids (VVV) project developed a series of extremely high-resolution N-body simulations to study haloes over the entire range of ΛCDM halo masses, from Earth mass to the largest clusters. In this talk, I will present our latest results about how baryons could modify these results for haloes with masses between 10^4 and 10^7 M_sun, below the threshold for galaxy formation. Our main study focuses on three simulations from identical initial conditions at z=127, one following dark matter only, one including non-radiative gas, and one additionally including the baryonic physics relevant in this mass range (cooling and photoheating). Using these simulations, we explore the baryonic impacts on halo abundance, density profile, and the dark matter annihilation signal from these haloes. An analytic model is also presented to clarify the impact of gas hydrodynamics and numerical issues on halo gas density profiles.
BIO
Dr. Haonan Zheng is a Boya & KIAA postdoc fellow at Peking University. He obtained his PhD degree from NAOC in the field of computational cosmology. His work mainly focuses on simulations of small-scale structures and their interactions with baryons. He is interested in the co-evolution between galaxies and haloes, and how these studies may shed light on the nature of dark matter.
Host: Pablo Renard
