Cloud properties across spatial scales in simulations of the interstellar medium
Context: Molecular clouds (MCs) are structures of dense gas in the interstellar medium (ISM) that extend from ten to a few hundred parsecs and form the main gas reservoir available for star formation. Hydrodynamical simulations of a varying complexity are a promising way to investigate MCs evolution...
Saved in:
| Main Authors: | , , , , , , , , , , , |
|---|---|
| Format: | Article (Journal) |
| Language: | English |
| Published: |
June 2024
|
| In: |
Astronomy and astrophysics
Year: 2024, Volume: 686, Pages: 1-29 |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/202348983 |
| Online Access: | Verlag, kostenfrei, Volltext: https://doi.org/10.1051/0004-6361/202348983 Verlag, kostenfrei, Volltext: https://www.aanda.org/articles/aa/abs/2024/06/aa48983-23/aa48983-23.html 
|
| Author Notes: | Tine Colman, Noé Brucy, Philipp Girichidis, Simon C.O. Glover, Milena Benedettini, Juan D. Soler, Robin G. Tress, Alessio Traficante, Patrick Hennebelle, Ralf S. Klessen, Sergio Molinari, and Marc-Antoine Miville-Deschênes |
| Summary: | Context: Molecular clouds (MCs) are structures of dense gas in the interstellar medium (ISM) that extend from ten to a few hundred parsecs and form the main gas reservoir available for star formation. Hydrodynamical simulations of a varying complexity are a promising way to investigate MCs evolution and their properties. However, each simulation typically has a limited range in resolution and different cloud extraction algorithms are used, which complicates the comparison between simulations. Aims: In this work, we aim to extract clouds from different simulations covering a wide range of spatial scales. We compare their properties, such as size, shape, mass, internal velocity dispersion, and virial state. Methods: We applied the HOP cloud detection algorithm on (M)HD numerical simulations of stratified ISM boxes and isolated galactic disk simulations that were produced using FLASH, RAMSES, and AREPO. Results: We find that the extracted clouds are complex in shape, ranging from round objects to complex filamentary networks in all setups. Despite the wide range of scales, resolution, and sub-grid physics, we observe surprisingly robust trends in the investigated metrics. The mass spectrum matches in the overlap between simulations without rescaling and with a high-mass power-law index of −1 for logarithmic bins of mass, in accordance with theoretical predictions. The internal velocity dispersion scales with the size of the cloud as σ ∝ R0.75 for large clouds (R ≳ 3 pc). For small clouds we find larger σ compared to the power-law scaling, as seen in observations, which is due to supernova-driven turbulence. Almost all clouds are gravitationally unbound with the virial parameter scaling as αvir ∝ M−04, which is slightly flatter compared to observed scaling but in agreement given the large scatter. We note that the cloud distribution towards the low-mass end is only complete if the more dilute gas is also refined, rather than only the collapsing regions. |
|---|---|
| Item Description: | Online veröffentlicht: 7. Juni 2024 Gesehen am 03.02.2025 |
| Physical Description: | Online Resource |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/202348983 |