Le 20 janvier 2017
De 10h30 à 12h00
Lorenzo POSTI
Kapteyn Institute, Groningen
Dynamical models play a crucial role in our understanding of the complex formation history and kinematics of galaxies. Stellar populations of different ages and chemistry typically show also diverse dynamics which reflects their formation/accretion history. I will present developments of novel analytic distribution function (DF) models which are specifically designed to self-consistently handle together different components with distinct kinematics. I will show applications of this formalism to a variety cases. i) Stellar halo of the Milky Way: using data from Gaia DR1 and RAVE DR5, I will present a metallicity-unbiased classification of halo stars based only on their 6D position-velocity and I will use it to asses the metallicity distribution of the local halo and the shape of the Galactic potential through the halo’s velocity ellipsoid. ii) dwarf Spheroidals: I will demonstrate the ability of such DF models to constrain the distribution of stars in different populations and dark matter from binned and un-binned spectroscopic data. iii) early-type galaxies (ETGs): multi-component DF models will be used to reproduce the Integral Field kinematics of some ETGs and to infer both the galaxy’s total mass distribution and the dynamical bulge/disc decomposition.