Disk kinematics & fragmentation in high-mass star formation: the link between observations and simulations

Aida Ahmadi

Thursday December 6th, 15:30

In recent years, differentially rotating disk-like structures have been observed surrounding the most luminous cores, making a case for high-mass star formation being a scaled-up version of low-mass star formation in this context. However, the fragmentation mode and the properties of these disk-like structures have yet to be comprehensively characterised. Using the IRAM NOrthern Extended Millimeter Array (NOEMA) and the IRAM 30-m telescope, the CORE survey has obtained high-resolution (~0.35", 700 AU at 2 kpc) observations of 20 well-known highly luminous star-forming regions in the 1.37 mm wavelength regime in both line and dust continuum emission. I will present our findings on the kinematics of the sample, using the disk tracer CH3CN. We find rotating structures surrounding the majority of our sample, making a case for disk-mediated accretion in high-mass star formation. We find that different fragmentation processes can contribute to the final stellar mass distribution within a single region, with core fragmentation on large scales and disk fragmentation on smaller spatial scales. We are able to study the Toomre stability of these structures and predict their fate in the disk fragmentation scenario. Furthermore, we use radiation hydrodynamic simulations to test the applied methods and investigate the limits of what current observations can unveil.