EPoS Contribution

Investigating high-mass star formation with ALMAGAL: Robust temperatures and luminosities of cores in a thousand high-mass cluster-forming regions Beth Jones UzK, Köln, DE
The ALMA Large Program ALMAGAL has observed over 1000 high-mass star forming clumps and unveiled the many ~1000 au protostellar cores embedded within. For the first time, homogeneous interferometric spectral line data are now available toward a significant fraction of the total Galactic population of high-mass star formation sites. Both determining the properties of protostellar cores within the Galaxy and the credibility range of parameters is vital to draw robust conclusions and truly understand the pathway from overdensities in molecular cloud clumps to Galactic high-mass stars. We present the first catalogue of temperatures and luminosities for over 1400 cores detected in CH3CN 12-11. From this, we determine not only reliable temperatures for the full evolutionary range of protostars, but the distributions of parameters that depend critically on temperature, such as luminosity and mass. We then explore the relative evolutionary state of the protostars embedded within a clump of a given luminosity-to-mass ratio, the fraction of clump luminosity powered solely by the cores, and quantify the correlation with other star formation features such as HII regions. To ensure the temperatures are robust, we probe degeneracies in derived parameters through massive MCMC realisations. We also present our exploration and results into novel methods to recover underlying density and temperature profiles through Machine Learning techniques, revealing insights into the limitations of using core-averaged properties in addition to deriving the observable profiles for comparison to simulations.

Caption: Temperature map of an ALMAGAL source based on CH3CN fitting (colour scale), using a single-layer model with XCLASS. The higher resolution dust continuum is overlaid as white contours. Two spectra (from lower: a hot core and upper: ambient envelope gas) are shown with their respective best fits, demonstrating the capability to determine temperatures for all sources in the ALMAGAL sample.
Collaborators: P. Schilke, UzK, DE T. Möller, UzK, DE A. Sanchez-Monge, ICE-CSIC, ES G. Stroud, JBCA, UK G. Fuller, JBCA, UK J. Beck, UzK, DE F. Niesel, FZJ, DE S. Kesselheim, FZJ, DE The ALMAGAL Collaboration	Relevant topic(s): Cores High-Mass SF
Relevant Big Question: How do the properties of individual protostellar cores influence their local gas environments within a high-mass star forming cluster?