Abstract

Poster - Splinter General   (MW-1801 / virtual plenum)

From Flows to Fragments: Tracking Core Evolution in Star-Forming Environments

Nuray Ortaköse, Michael Weis, Stefanie Walch
Universität zu Köln

Observations show that stars form in large filamentary networks within molecular clouds. The degree of fragmentation can vary significantly within the same cloud. Several theoretical frameworks have been proposed to explain these observations. The main competing models can be broadly divided into core-fed and clump-fed scenarios. In the core-fed picture, stellar masses are largely set by the initial core mass, whereas in clump-fed models, stars accrete mass from extended regions within a dynamic, clustered environment. In this work, we investigate how gas dynamics regulate fragmentation and accretion in an existing colliding-flow simulation of the warm neutral medium. We also aim to understand how these dynamics influence the formation and growth of massive cores. We develop a tracking framework that combines dendrogram-based density hierarchies of the gas with tracer particles, which follow the gas velocity field. This approach is designed to preserve both the evolving density structure and the physical history of the gas. The tracking analysis is complemented by measurements of tracer and gas mass transport, radial shell diagnostics, and an Eulerian virial analysis to quantify how environmental inflows effect the dynamical evolution of the cores. A central result of this thesis is that the surrounding clump plays a large role in regulating core growth and dynamics in the central region around the core. Furthermore, the dynamical coupling between cores and their environments differs between individual systems. Some cores evolve in a relatively coherent manner across spatial scales, while other cores are strongly connected to a dynamically active clump. The degree of fragmentation within these systems appears to be connected to how efficient the central region remains coupled to its parent clump.