{"paper_id":"0b16336b-b1b3-46b7-98e9-c62a080455ce","body_text":"A Solar Like Magnetic Reconnection Event in the Corona of a Supermassive Black Hole | 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 A Solar Like Magnetic Reconnection Event in the Corona of a Supermassive Black Hole Gal Vardi, Ehud Behar, Liyi Gu, Jelle Kaastra, Matteo Guainazzi, and 11 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8803757/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 The X-ray source around supermassive black holes in active galactic nuclei (AGN) has been dubbed the corona by analogy to the solar (and stellar) corona. Both stellar and AGN coronae are orders of magnitude hotter than their counterpart optical source; the stellar photosphere and accretion disk respectively. Both coronae vary on short time scales down to seconds. The coronal activity in the Sun is well imaged and its activity has been shown to be driven by magnetic energy converted into heat through the process of magnetic reconnection. While it has been theorized that AGN corona are also magnetically driven, the driving mechanism of AGN coronal activity has not been directly observed. A smoking gun of magnetic reconnection is when a coronal flare’s temporal evolution in hard and soft X-rays follows the Neupert Effect. These flares result in both a solar coronal mass ejection, and energetic particles streaming down along magnetic field lines to the photosphere. Here, we report the detection of the Neupert Effect in an AGN corona, providing the first direct evidence for magnetic reconnection in AGN. Our measurements indicate a magnetic field loop height of up to 30 gravitational radii, and a distance of about 400 gravitational radii between the corona and the UV emitting accretion disk. The present findings thus enable the application of solar coronal physics to the less accessible AGN corona. Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/High-energy astrophysics Physical sciences/Physics/Astronomy and astrophysics/Astrophysical magnetic fields 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. 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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-8803757\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":true,\"archivedVersions\":[],\"articleType\":\"Physical Sciences - Article\",\"associatedPublications\":[],\"authors\":[{\"id\":596401830,\"identity\":\"a2532b4e-bf04-45ab-b115-ae377bf69321\",\"order_by\":0,\"name\":\"Gal 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