Modelling star formation and feedback in local galaxies
Title: Modelling star formation and feedback in local galaxies
SNIC Project: SNIC 2021/5-437
Project Type: SNIC Medium Compute
Principal Investigator: Angela Adamo <>
Affiliation: Stockholms universitet
Duration: 2021-10-01 – 2022-10-01
Classification: 10305


Galaxies form and evolve by converting their gas into stars. However, observations of all galaxy types and masses reveal that this process is highly inefficient. Understanding and quantifying the reasons of this inefficiency is the central question in the field of galaxy evolution. The processes of stellar feedback (e.g. supernovae) regulates the cycle of gas consumption by ejecting the gas out of the star forming regions, and making it too hot to immediately form stars. This induces delays in the star formation process, in a very complex and not fully understood manner. The main difficulty consists in describing the coupling of these effects with the larger galactic scales, which strongly depends on the environment (e.g. galactic center vs. spiral arms). Our team has recently obtained observational data at unprecedented resolution of the spiral galaxy M83, with the MUSE instrument on the Very Large Telescope, as well as with the WFC3 camera on-board the Hubble Space Telescope. By combining these observations with data from the ALMA array of radio telescopes, we are building detailed maps of the physical conditions of star formation and stellar feedback across the galactic disc, i.e. in a wide diversity of environments (Della Bruna et al. submitted, Adamo et al. in prep.). The wealth of data obtained will lead to a series of publications in the next years (at least 10 papers planned). The proposed SNIC project constitutes the theoretical complement of this large program. We will run an hydrodynamical model of M83 reproducing the grand-design spiral pattern and the bar, with the RAMSES code at a resolution of a few parsec to resolve the star forming regions. We will then study how feedback regulates star formation over the diversity of environments found in the galaxy. Our simulations will be constrained by the observations: we will build a model of a grand-design spiral galaxy resembling M83 using the well-tested Multiple Gaussian Extension technique (MGE, Emsellem et al. 1994). This model will complement the observations by providing access to the time dimension, such that we will be able to track the evolution of the various star forming regions, in the galactic nucleus, in the spiral arms, in the inter-arm regions. We will create mock observations (photometric and kinematic maps) for a direct comparison of our simulation with the real galaxy. The simulations will provide easy access to quantities notoriously difficult or impossible to measure observationally: timescales, accelerations, shear, 3D structures of feedback signature etc. All these new dimensions will constitute a fundamental complement to the observations, and will be a critical asset to interpret them.