Driven by gravity, galaxies continuously grow through accretion of smaller systems. Stellar streams are nice illustrations of this hierarchical build-up, but the accreted stars quickly disperse. I will present advanced dynamical models that can convert the observed positions and velocities of stars to phase-space quantities like energy and angular momentum which remain largely conserved. In addition, these models can include the observed ages and chemical properties of stars which are also conserved. The resulting population-dynamical models allow us then to uncover even those accretion events which are now fully dispersed. At the same time, these models also accurately constrain the total mass distribution, including a central black hole and dark matter halo. I will illustrate how these models make optimally use of observations to unveil the dark side and colour past of galaxies: from accurate measurements of their central black holes and extended dark halos, to unveiling the formation history of their disks, to uncovering ancient massive mergers and accreted satellite galaxies. By the end, I aim to have demonstrated that these models provide a unique bridge between the studies of resolved stars in the Milky Way and integrated-light of high(er)-redshift galaxies. Together with direct coupling to state-of-the-art galaxy formation simulations, these population-dynamical models enable us to uncover the hierarchical build-up of galaxies in a cosmological context.
学术报告
The colourful past and dark side of galaxies unveiled through population-dynamics of their stars
报告题目：The colourful past and dark side of galaxies unveiled through population-dynamics of their stars
报 告 人：Glenn van de Ven (University of Vienna)
报告时间：2025-09-18 16:10:00
报告地点：Hall 212, Astronomy Building
Abstract:
Biography: I am Full Professor of Theoretical Extragalactic Astrophysics in the Department of Astrophysics at the University of Vienna since March 2019. My research group (https://dynamics.univie.ac.at) is one of the few in the world that has the expertise and machinery to construct detailed dynamical models of globular clusters and nearby galaxies. This enables us to infer the luminous and dark matter distribution of these stellar systems, as well as to uncover their formation history. Our pioneering code for orbital modelling of stellar systems is today publicly released under the name DYNAMITE (http://www.ascl.net/code/v/2684). Since 2010, I have successfully built a diverse research group (>50% women) with various MSc, BSc and summer students and so far 16 PhD students and 17 postdocs, many of them supported through third-party funds. I am also actively contributing to the astronomical society: from being a core member of leading international collaborations such as the CALIFA Survey, Fornax Deep Survey, Fornax 3D Survey, to discussions leader and principal organiser of numerous international meetings.