Design and Operational Strategies for Mitigating Static After Cavity Interaction in High-Power Gyrotrons

Design and Operational Strategies for Mitigating Static After Cavity Interaction in High-Power Gyrotrons | 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 Design and Operational Strategies for Mitigating Static After Cavity Interaction in High-Power Gyrotrons André Schmidt, Konstantinos Avramidis, Lukas Feuerstein, Stefan Illy, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8986737/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract Gyrotrons are essential sources for electron cyclotron resonance heating in magnetic confinement fusion devices. Achieving high overall efficiency and the nominal design power in these devices is a critical requirement. However, discrepancies between theoretical models and experimental results often arise because real systems exhibit additional effects that are not fully captured in idealized simulations. One such effect is the static After-Cavity Interaction (ACI) of the same transverse electric (TE) mode in the cavity uptaper and quasi-optical launcher, which can significantly reduce performance. A thorough understanding of ACI, supported by advanced simulation tools, is essential to identify effective mitigation strategies. Practical measures include fine adjustments of the magnetic field, operation at alternative working points, or modifications to the launcher geometry. Such approaches offer promising potential to enhance overall efficiency in gyrotrons for present and future fusion applications. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 24 Mar, 2026 Reviews received at journal 24 Mar, 2026 Reviewers agreed at journal 16 Mar, 2026 Reviews received at journal 13 Mar, 2026 Reviewers agreed at journal 05 Mar, 2026 Reviewers invited by journal 02 Mar, 2026 Editor assigned by journal 02 Mar, 2026 Submission checks completed at journal 02 Mar, 2026 First submitted to journal 27 Feb, 2026 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-8986737","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":599566144,"identity":"4b5ccbfc-14c9-4f16-83a1-e181aa7ad6bf","order_by":0,"name":"André 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