From Snapshots to Movies – From nearby-observations of feedback to a time theory dependent star-formation

In Webseminar by admin

Wednesday 22 July 2020 11AM
Eric Pellegrini (University of Heidelberg, Institute of Theoretical Astrophysics)
Historically models of star forming regions in the forms of HII regions and PDRs  face a fundamental limitation of reproducing present day conditions independent of cloud evolution which limits our understand of feedback to instantaneous physics. I will discuss the WARPFIELD-EMission Predictor, WARPFIELD-EMP, which couples the 1D stellar feedback code WARPFIELD with the Cloudy HII region/PDR code and the POLARIS radiative transfer code, in order to make detailed predictions for the time-dependent line and continuum emission arising from the HII region and PDR surrounding an evolving star cluster. WARPFIELD-EMP accounts for a wide range of physical processes (stellar winds, supernovae, radiation pressure, gravity, thermal conduction, radiative cooling, dust extinction etc.) and yet runs quickly enough to allow us to explore broad ranges of different cloud parameters. I compare the results of an extensive set of models with SITELLE observations of a large sample of HII regions in NGC~628 and find very good agreement, particularly for the highest signal-to-noise observations. This allows us to create a novel method to model galactic scale star formation and the resulting emission from star clusters and the multi-phase interstellar medium. I combine global parameters, such as SFR and CMF, with WARPFIELD. The heating of diffuse gas and dust is calculated self-consistently with the age, mass and density dependent escape fractions of the local star-forming regions. From this the interstellar radiation field at any point in the galaxy is reconstructed to produce synthetic emission maps for the one-to-one comparison with observational data. Finally, I will discuss what these results mean for our understanding of star-formation feedback.