240:Institute of Theoretical Physics and Astrophysics Seminar Series

, 2016/12/05
Dr Dong

Title: Testing cold dark matter vs. modified gravity with Milky Way's stellar kinematic data

Speaker:Xiaobo Dong, Research Fellow
Unit:Yunnan Astronomical Observatory
Time:2016.12.05(Monday) 14:30
Place:Physics Building 407, Haiyun Campus, Xiamen University
Abstract: Using for the first time both the rotation curve data V_rot(R) and the vertical velocity dispersion data sigma(R) of the Milky Way (MW) stars, we test and verify the self-consistency of the quasi-linear formulation of modified newtonian dynamics (QUMOND, Milgrom 2010).
Then, using QUMOND as an effective/practical tool and based purely on the baryonic distribution of the MW, we derive the 3-dimensional distribution of the effective gravitational field (Phi_phantom) of the putative dark matter (DM) halo in the popular DM paradigm. The effective gravitational field Phi_phantom appears not easy to realize with commonly used density profiles of CDM theory.
Lastly we propose expects for mapping the 3-dimensional MW's gravitational field in the LAMOST and GAIA era.