Orateur
Description
Using Gaia proper motions, several studies in the last few years have pointed to a declining rotation curve of the Milky Way beyond 20 kpc. One study found that this decline is Keplerian like in our Solar System, suggesting a sharp truncation of the dark matter density profile. This would require to either drop the standard model of the mass density of the Universe dominated by cold dark matter, or that our Galaxy has suffered from tidal truncation from a more massive and concentrated object. I will describe the results of a new re-analysis of the Gaia data, which would be the first bayesian analysis on a star by star basis, properly including (for the 1st time) all terms in the stationary axisymmetric Jeans equation of local dynamical equilibrium, using a novel, yet general set of priors.
