Coronal Magnetic Field Modulates Giga-electronvolt Solar Disk Gamma Rays

Coronal Magnetic Field Modulates Giga-electronvolt Solar Disk Gamma Rays | 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 Coronal Magnetic Field Modulates Giga-electronvolt Solar Disk Gamma Rays Chingam Fong, Zhe Li, Kenny.Chunyu NG This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8862901/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 disk gamma rays, theorized to originate from hadronic galactic cosmic-ray interactions, exhibit many puzzling features. At 1 giga-electronvolts (GeV), these features include high flux and anti-correlation with the solar activity cycle. Between 10 and 50 GeV, it also displays an unexpected time- and energy- dependent morphology. A key question is how solar magnetic fields could affect solar disk gamma rays. The magnetic field in solar corona, in particular, is complex in structure, variable in time, and difficult to probe. Here we present the first model of time-dependent gamma-ray flux across an entire solar cycle, produced using simulation toolkit G4SOLAR and incorporating state-of-the-art coronal magnetic field models. Our result produces good agreement with observations in both flux and time variation between 0.1 and 1 GeV, showing the open coronal fields as the dominant cause. We further predict distinct morphological signatures linked to coronal magnetic field structures, which can be verified by future gamma-ray telescopes. These findings establish a clear connection between coronal field and GeV gamma-ray emission, positioning solar gamma rays as a novel tool to study solar physics. Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/High-energy astrophysics Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/Particle astrophysics Physical sciences/Physics/Space physics/Solar physics Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/Computational astrophysics Solar disk gamma ray Coronal magnetic field Galactic cosmic-ray transport Solar cycle time variability Full Text Additional Declarations There is NO Competing Interest. Supplementary Files MovieS2.mp4 Rotating snapshot of our simulation for CR 2193 and protons between 10 and 100 GeV, and gamma ray between 1 and 10 GeV MovieS1.mp4 Rotating snapshot of our simulation for CR 2193 and protons between 1 and 10 GeV, and gamma ray between 0.1 and 1 GeV MovieS5.mp4 Rotating snapshot of our simulation for CR 2193 and protons between 10 and 100 TeV, and gamma ray between 1 and 10 TeV. MovieS4.mp4 Rotating snapshot of our simulation for CR 2193 and protons between 1 and 10 TeV, and gamma ray between 100 GeV and 1 TeV MovieS3.mp4 Rotating snapshot of our simulation for CR 2193 and protons between 100 GeV and 1 TeV, and gamma ray between 10 and 100 GeV 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. 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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-8862901","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":599237596,"identity":"1d83ddcc-6583-46a2-bb8d-e5edcb885767","order_by":0,"name":"Chingam 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