Vertical Gas Circulation in Star-Forming Galaxies: Near-Equilibrium between Star Formation and Gravity

Vertical Gas Circulation in Star-Forming Galaxies: Near-Equilibrium between Star Formation and Gravity | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Physical Sciences - Article Vertical Gas Circulation in Star-Forming Galaxies: Near-Equilibrium between Star Formation and Gravity Yucheng Guo, Timothy Heckman, Matthew Lehnert, Sanchayeeta Borthakur, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6568372/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Gas accretion and feedback are fundamental processes in galaxy evolution models and simulations. In particular, feedback from massive stars is thought to reshape the structure of the interstellar medium (ISM) and self-regulate star formation, leading to the tight observed relationship between star formation rate (SFR) and galaxy mass. However, direct observational constraints on this feedback loop remain limited. Most studies either focus on small samples of galaxies or predominantly probe the warm and hot ionized gas phases, leaving the impact of feedback on the cold neutral gas -- a critical phase of the ISM -- largely unexplored. To address this, we use single-dish HI 21cm observations to statistically detect bulk vertical motions of neutral hydrogen in a sample of nearby, star-forming galaxies. These motions trace gas flows moving perpendicular to the galactic disk. Our analysis reveals that the vertical gas flows exist in a near-equilibrium state: they are driven outwards as galactic winds by momentum injection from star formation, while being simultaneously pulled back by gravitational forces, forming a fountain-like cycle. Such galactic fountains are prevalent in the local Universe. Their mass, momentum, and kinetic energy scale with SFR and can be well explained by a simple dynamical model balancing stellar feedback and gravity. This supports a scenario in which gas recycling, rather than complete ejection, is the dominant outcome of stellar feedback in the local Universe, highlighting the importance of vertical gas circulation in regulating star formation. Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/Galaxies and clusters Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/Interstellar medium Full Text Additional Declarations There is NO Competing Interest. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6568372","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Physical Sciences - Article","associatedPublications":[],"authors":[{"id":455229982,"identity":"535bfd2d-9d69-413c-b26e-9d313f6283c9","order_by":0,"name":"Yucheng 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