Speaker
Description
Star formation, particularly in massive star-forming regions, is a complex, multi-scale process.
To explore the fundamental mechanisms driving the collapse of parsec-scale clumps, ultimately shaping the star-formation outcome, the Rosetta Stone project was developed. This project provides an end-to-end (simulations ⇔ observations) framework for comparing observational data with numerical simulations by systematically generating synthetic observations of clump fragmentation. Such approach enables a self-consistent, quantitative analysis of how the initial conditions of clump collapse influence the observed fragmentation properties.
As a first case study, ALMA 1.3 mm continuum dust emission observations from the SQUALO survey have been compared with a tailored set of post-processed radiative magneto-hydrodynamical simulations of high-mass clump fragmentation.
The numerical models have been initialized combining typical values of clump mass (500 and 1000 M$_\odot$) and radius (∼0.4 pc), with two levels of turbulence (Mach number 𝓜 of 7 and 10), and three levels of magnetization (normalized mass to magnetic flux ratio $\mu$ of ∼3, 10 and 100). They have been post-processed tuning the CASA software to replicate the SQUALO project observing strategy, combining ACA and the 12 m array.
A statistically robust set of ∼1000 synthetic maps, collected from following clump evolution over time and along three orthogonal directions, reveals that clump fragmentation extends beyond the initial stages of collapse. Furthermore, fragments continuously accrete mass from the parent clump, remaining tightly coupled to the environment. Among the adopted initial conditions, magnetic fields emerge as the most influential factor in determining the fragmentation outcome at ∼7000 AU scales, with magnetized clumps producing fewer fragments.
These initial results demonstrate how the systematic production of synthetic observations could provide a fresh perspective on the physics of clump fragmentation.
