The Sagittarius dwarf galaxy has a disk with a Λ-like metallicity profile

The Sagittarius dwarf galaxy has a disk with a Λ-like metallicity profile | 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 Article The Sagittarius dwarf galaxy has a disk with a Λ-like metallicity profile Xiang-Xiang Xue, Zixi Guo, Chao Liu, Jiang Chang, Zehao Zhong, and 8 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7248521/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Unveiling the properties of the progenitors that formed the tidal structures of the Milky Way (MW) is essential for exploring the MW's assembly history. Such studies further afford a unique opportunity to dissect the formation and evolution of dwarf galaxies by contrasting surviving and disrupted systems. However, reconstructing the intrinsic structure of progenitors solely from the positions and velocities of their tidal debris remains a formidable challenge. Here, we decode the chemo-kinematical signatures embedded in the stellar streams of the Sagittarius (Sgr) dwarf galaxy through N-body simulations. For the first time, we reproduce a vertical metallicity gradient in the Sgr streams, which we attribute to a disk-dominated progenitor with a Λ-like metallicity profile across the disk. Remarkably, similar metallicity profiles are identified in MaNGA survey data for several field dwarf galaxies, suggesting this feature is not unique to Sgr. The vertical metallicity gradient of stellar streams preserves extra detailed galactic fossil records, enabling quantitative reconstruction of the peculiar structure of the satellite galaxy. The similar metallicity profile of Sgr to MW opens a question on a possible special coevolution. Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/Computational astrophysics Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/Galaxies and clusters Full Text Additional Declarations There is NO Competing Interest. Supplementary Files methodsgr.pdf Method of The Sagittarius dwarf galaxy has a disk with a Λ-like metallicity profile Cite Share Download PDF Status: Under Review 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. 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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-7248521","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":509790278,"identity":"4fc06514-082b-44ee-9924-12895fa36e95","order_by":0,"name":"Xiang-Xiang 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