Investigation of the Indirect Neupert Effect in Five Solar Flares

Investigation of the Indirect Neupert Effect in Five Solar Flares | 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 Research Article Investigation of the Indirect Neupert Effect in Five Solar Flares Xiaoyu Tang, Zongjun Ning, Yuzhi Yang, Yuxiang Song, Yijie Han, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7747005/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract The Neupert effect is characterized by the strong correlation between the time derivative of the soft X-ray (SXR) flux and the hard X-ray (HXR) or microwave flux in solar flares. Based on the standard flare model, the nonthermal electrons responsible for SXR, HXR, as well as microwave emissions and those producing solar meter-wave type III radio bursts originate simultaneously from magnetic reconnection with the opposite directions, i.e., downward and upward. Therefore, it is reasonable that the upward nonthermal electrons exhibit the same characteristics as the downward electrons. Observationally, the meter-wave type III radio bursts should be correlated with the SXR derivative, which is the indirect Neupert effect. In this paper, we analyzed the correlations between the solar meter-wave type III radio bursts observed by Chashan broadband solar radio spectrometer at meter wavelengths (CBSm) and the SXR derivative at 1-8 Å measured by Geostationary Operational Environmental Satellite (GOES), the HXR at 15-25 or 25-50 keV measured by Spectrometer/Telescope for Imaging X-rays (STIX), and the microwave measured by Nobeyama Radio Polarimeters (NoRP) in five solar flares. Firstly, we find a high correlation between the meter-wave type III radio bursts and the SXR derivative, indicating that these five flares follow the indirect Neupert effect. Secondly, we find a high correlation between the meter-wave type III radio bursts and both HXR and microwave emissions, which is consistent with the magnetic reconnection to accelerate the bi-directional electrons. Flares Neupert effect Solar radio emission X-ray emission Mcrowave emission Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 10 Nov, 2025 Reviewers invited by journal 13 Oct, 2025 Editor assigned by journal 03 Oct, 2025 Submission checks completed at journal 03 Oct, 2025 First submitted to journal 30 Sep, 2025 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-7747005","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":529445974,"identity":"43544ba9-0079-4a9a-9a99-35965004d457","order_by":0,"name":"Xiaoyu 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Based on the standard flare model, the nonthermal electrons responsible for SXR, HXR, as well as microwave emissions and those producing solar meter-wave type III radio bursts originate simultaneously from magnetic reconnection with the opposite directions, i.e., downward and upward. Therefore, it is reasonable that the upward nonthermal electrons exhibit the same characteristics as the downward electrons. Observationally, the meter-wave type III radio bursts should be correlated with the SXR derivative, which is the indirect Neupert effect. 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Secondly, we find a high correlation between the meter-wave type III radio bursts and both HXR and microwave emissions, which is consistent with the magnetic reconnection to accelerate the bi-directional electrons.","manuscriptTitle":"Investigation of the Indirect Neupert Effect in Five Solar Flares","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-27 11:12:00","doi":"10.21203/rs.3.rs-7747005/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"288283834742380198170643492430664950672","date":"2025-11-10T09:41:10+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-13T04:39:34+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-03T13:08:32+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-03T13:07:27+00:00","index":"","fulltext":""},{"type":"submitted","content":"Solar Physics","date":"2025-09-30T04:14:04+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"solar-physics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"sola","sideBox":"Learn more about [Solar Physics](http://link.springer.com/journal/11207)","snPcode":"11207","submissionUrl":"https://submission.nature.com/new-submission/11207/3","title":"Solar Physics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"7b398d75-3e25-4271-b809-27d5b174209d","owner":[],"postedDate":"October 27th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-10-27T11:12:00+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-27 11:12:00","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7747005","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7747005","identity":"rs-7747005","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}