Constraining turbulent solar flare acceleration by connecting kinetic modeling and X-ray observations

Constraining turbulent solar flare acceleration by connecting kinetic modeling and X-ray observations | 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 Constraining turbulent solar flare acceleration by connecting kinetic modeling and X-ray observations Morgan Stores, Natasha Jeffrey, Ewan Dickson, James McLaughlin, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6502645/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 Spatially-resolved X-ray observations are the key to understanding electron acceleration in solar flares. Currently, the underlying processes that efficiently energize solar flare particles are poorly constrained. Abundant flare observations suggest that turbulence plays a crucial role in transferring energy between the magnetic field and energetic electrons. For the first time, we connect turbulence and hard X-ray observations with kinetic modeling to constrain the properties of flare acceleration. Observing three large flares with RHESSI, or Solar Orbiter/STIX, we extract X-ray imaging and spectroscopy observables. We compare with modeling results, mapping observables to electron acceleration and turbulent properties. We determine that extended regions of turbulence are required to match multiple X-ray observables, suggesting electrons are accelerated over a large fraction (~25%) of the flare loop; a property that has previously been unconstrained. Additionally, we determine acceleration timescales that vary between 7 and 22s; a property that will help to restrict possible viable stochastic models. Physical sciences/Astronomy and planetary science/Space physics/Solar physics Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/High-energy astrophysics 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. 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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-6502645","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":456158668,"identity":"5c387e88-0bc8-4d12-8677-32ed054e5cf6","order_by":0,"name":"Morgan Stores","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAApUlEQVRIiWNgGAWjYBADOQjFRpRiZjBpTLqWxAaitej2nz/4uKKiLn3DtbMHGD6UHSasxexGMrPhmTOHczfczktgnHGOKC3MbJKNbQeAWnIMmHnbiNFy/jBQy7+6dAOQlr9EaTmQDNTSwJwA1sJIlJYbycaGDccOG84EajnYcy6dGIcdfPiwoaZOnu92juGDH2XWhLWggAMkqh8Fo2AUjIJRgAsAAJs7O/uNJ6a6AAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0002-6060-8048","institution":"UCAR","correspondingAuthor":true,"prefix":"","firstName":"Morgan","middleName":"","lastName":"Stores","suffix":""},{"id":456158669,"identity":"6492c476-fcd9-4c11-bd2c-18e4a502f272","order_by":1,"name":"Natasha Jeffrey","email":"","orcid":"https://orcid.org/0000-0001-6583-1989","institution":"Northumbria University","correspondingAuthor":false,"prefix":"","firstName":"Natasha","middleName":"","lastName":"Jeffrey","suffix":""},{"id":456158670,"identity":"4a4c1ee8-42d4-419d-911c-19f0fa23735b","order_by":2,"name":"Ewan Dickson","email":"","orcid":"","institution":"The Royal Observatory of Belgium","correspondingAuthor":false,"prefix":"","firstName":"Ewan","middleName":"","lastName":"Dickson","suffix":""},{"id":456158671,"identity":"d46c16dd-f8b9-4d3c-8bc7-ff514e4b769f","order_by":3,"name":"James McLaughlin","email":"","orcid":"https://orcid.org/0000-0002-7863-624X","institution":"Northumbria University","correspondingAuthor":false,"prefix":"","firstName":"James","middleName":"","lastName":"McLaughlin","suffix":""},{"id":456158672,"identity":"400ea268-94f4-434c-8e88-50ae53859e00","order_by":4,"name":"Eduard Kontar","email":"","orcid":"https://orcid.org/0000-0002-8078-0902","institution":"University of Glasgow","correspondingAuthor":false,"prefix":"","firstName":"Eduard","middleName":"","lastName":"Kontar","suffix":""}],"badges":[],"createdAt":"2025-04-22 09:32:46","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6502645/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6502645/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":93035501,"identity":"6153be75-d927-48bd-b30a-8f43ff1bf2fc","added_by":"auto","created_at":"2025-10-08 11:04:52","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3975395,"visible":true,"origin":"","legend":"Article File","description":"","filename":"Storesmanuscriptdraft.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6502645/v1_covered_16bda9e7-a2b7-4cff-9456-1da2ee683724.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Constraining turbulent solar flare acceleration by connecting kinetic modeling and X-ray observations","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6502645/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6502645/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Spatially-resolved X-ray observations are the key to understanding electron acceleration in solar flares. 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