{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/a-new-method-for-spatially-resolving-the","title":"A new method for spatially resolving the turbulence driving mixture in the ISM with application to the Small Magellanic Cloud","arxiv_id":"2309.10755","date":"2023-09-19","proceeding":null,"authors":["Isabella A. Gerrard","Christoph Federrath","Nickolas M. Pingel","Naomi M. McClure-Griffiths","Antoine Marchal","Gilles Joncas","Susan E. Clark","Snežana Stanimirović","Min-Young Lee","Jacco Th. van Loon","John Dickey","Helga Dénes","Yik Ki Ma","James Dempsey","Callum Lynn"],"abstract":"Turbulence plays a crucial role in shaping the structure of the interstellar medium. The ratio of the three-dimensional density contrast ($\\sigma_{\\rho/\\rho_0}$) to the turbulent sonic Mach number ($\\mathcal{M}$) of an isothermal, compressible gas describes the ratio of solenoidal to compressive modes in the turbulent acceleration field of the gas, and is parameterised by the turbulence driving parameter: $b=\\sigma_{\\rho/\\rho_0}/\\mathcal{M}$. The turbulence driving parameter ranges from $b=1/3$ (purely solenoidal) to $b=1$ (purely compressive), with $b=0.38$ characterising the natural mixture (1/3~compressive, 2/3~solenoidal) of the two driving modes. Here we present a new method for recovering $\\sigma_{\\rho/\\rho_0}$, $\\mathcal{M}$, and $b$, from observations on galactic scales, using a roving kernel to produce maps of these quantities from column density and centroid velocity maps. We apply our method to high-resolution HI emission observations of the Small Magellanic Cloud (SMC) from the GASKAP-HI survey. We find that the turbulence driving parameter varies between $b\\sim 0.3$ and $b\\sim 1.0$ within the main body of the SMC, but the median value converges to $b\\sim0.51$, suggesting that the turbulence is overall driven more compressively ($b>0.38$). We observe no correlation between the $b$ parameter and HI or H$\\alpha$ intensity, indicating that compressive driving of HI turbulence cannot be determined solely by observing HI or H$\\alpha$ emission density, and that velocity information must also be considered. Further investigation is required to link our findings to potential driving mechanisms such as star-formation feedback, gravitational collapse, or cloud-cloud collisions.","url_abs":"https://arxiv.org/abs/2309.10755v1","url_pdf":"https://arxiv.org/pdf/2309.10755v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"a-new-method-for-spatially-resolving-the","repo_url":"https://github.com/igerrard/b_finder","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}