Unipolar Network Microflashes as Nanoflares that Power Corona and Solar Wind

Unipolar Network Microflashes as Nanoflares that Power Corona and Solar Wind | 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 Unipolar Network Microflashes as Nanoflares that Power Corona and Solar Wind Navdeep K. Panesar, Sanjiv Tiwari, Meng Jin, Ayla Weitz, Ronald Moore, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6239847/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 Solar plumes – outflows of bright coronal plasma – are a major component of the open-magnetic-field corona and solar wind, but their driving remains uncertain. Here, we report “network microflashes,” fine-scale bright bursts captured by Solar Orbiter’s Extreme Ultraviolet Imager in 174A images encompassing magnetic network at the base of plumes. Unlike conventional small-scale solar jets, which arise in mixed-polarity magnetic field, network flashes occur in apparently unipolar magnetic field. Approximately 20 microflares are ongoing within a plume base, with a new microflash starting every second. The energy for an average microflash is 10^24 erg, in the range of nanoflares. We use a 3D data-driven global MHD model that yields open magnetic field with fast solar wind for the investigated plumes. Our findings suggest that network flashes result from fine-scale bursts of reconnection of crossed legs of unipolar magnetic field, that the bursts are often triggered by 5-minute p-mode oscillations, and that the bursts power the open-field corona and solar wind. This study opens a new window on the driving of solar coronal heating and solar wind acceleration. Physical sciences Physical sciences/Physics/Astronomy and astrophysics/Stars Full Text Additional Declarations There is NO Competing Interest. Supplementary Files MOVIE1.mp4 Examples of network flashes at a plume base observed on 29-Mar-2023 MOVIE2.mp4 Examples of network flashes at a plume base observed on 26-Oct-2023 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-6239847","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":456943960,"identity":"5444e8bb-3bec-4caa-bd1f-979b46ae0621","order_by":0,"name":"Navdeep K. 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Here, we report “network microflashes,” fine-scale bright bursts captured by Solar Orbiter’s Extreme Ultraviolet Imager in 174A images encompassing magnetic network at the base of plumes. Unlike conventional small-scale solar jets, which arise in mixed-polarity magnetic field, network flashes occur in apparently unipolar magnetic field. Approximately 20 microflares are ongoing within a plume base, with a new microflash starting every second. The energy for an average microflash is 10^24 erg, in the range of nanoflares. We use a 3D data-driven global MHD model that yields open magnetic field with fast solar wind for the investigated plumes. Our findings suggest that network flashes result from fine-scale bursts of reconnection of crossed legs of unipolar magnetic field, that the bursts are often triggered by 5-minute p-mode oscillations, and that the bursts power the open-field corona and solar wind. 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