Visible emission line spectroscopy of the solar corona during the 2019 total solar eclipse

Visible emission line spectroscopy of the solar corona during the 2019 total solar eclipse | 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 Visible emission line spectroscopy of the solar corona during the 2019 total solar eclipse Gabriel Domingo Muro, Matt Gunn, Stephen Fearn, Tomos Fearn, Huw Morgan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2538179/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 12 Jun, 2023 Read the published version in Solar Physics → Version 1 posted 7 You are reading this latest preprint version Abstract Spectroscopic measurements of the low solar corona are crucial to understanding the mechanisms that heat the corona and accelerate the solar wind, yet the lowest solar radii (R⊙) of the corona is difficult to observe. Our expedition collected narrow wavelengths of visible light at 530.3, 637.4, and 789.2 nm emitted by Fe XIV, X, and XI ions, respectively, from the total solar eclipse on 2019 July 2 at 20:40 UTC in Rodeo, Argentina with a bespoke 3-channel spectrometer. This paper describes the instrument, and data calibration method that enables diagnostics out to ≈1.0 R⊙ above the solar limb within a bright helmet streamer. We find that Fe X and XI lines are dominant through 0.3 R⊙, with Fe XIV maintaining a stronger signal at higher elevations. Thermal broadening is consistent with 4 MK for the cooler Fe X and XI lines, and 6 MK for the hottest Fe XIV line, which can be interpreted as differing density scale heights within isolated, isothermal flux tubes. The Doppler measurements correspond to bulk plasma motion ranging from -12 to +2.5 km s-1, with Fe XIV moving at nearly an assumed solid body rotation rate throughout 1.0 R⊙. After considering coronal rotation, these measurements are likely associated with plasma motion along the dominant longitudinal orientation of the magnetic field at the streamer base within 0.4R⊙. These results show that high resolution spectroscopy of visible light offers valuable diagnostics of the low corona, and lend insight into the interconnected loop complexity within helmet streamers. eclipse visible light spectroscopy dynamics magnetic fields corona Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 12 Jun, 2023 Read the published version in Solar Physics → Version 1 posted Editorial decision: Major revision 07 Mar, 2023 Reviews received at journal 25 Feb, 2023 Reviewers agreed at journal 03 Feb, 2023 Reviewers invited by journal 03 Feb, 2023 Editor assigned by journal 02 Feb, 2023 Submission checks completed at journal 02 Feb, 2023 First submitted to journal 01 Feb, 2023 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-2538179","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":172672092,"identity":"eef937a2-bbe4-4cf0-85d4-be55c7e0e94e","order_by":0,"name":"Gabriel Domingo Muro","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAzElEQVRIiWNgGAWjYFACHgjFDyISCkjRItkA0mJAihaDA2CSCA3y7mcPPrrZdk/O+PzqxA8PDBjk+cUO4NdieCYv2Ti3rdjY7MbbzRJAhxnOnJ1AQEtDjpl0bltC4rYbZzeAtCQY3Cakpf+N+W+Qls0zzm7+QZQWeYkcM2aQlg38vduIs8VA4l2ydM65BGOJG7zbLBIMJAj7Rb4/9+DnnLIEOf7+s5tv/qiwkeeXJmTLARhLAqxSAr9ysC0NMBb/AdyqRsEoGAWjYGQDAP0NRNx1+pPmAAAAAElFTkSuQmCC","orcid":"","institution":"Aberystwyth University","correspondingAuthor":true,"prefix":"","firstName":"Gabriel","middleName":"Domingo","lastName":"Muro","suffix":""},{"id":172672093,"identity":"006d7d9c-2945-44c5-ac89-e70f2a3379ae","order_by":1,"name":"Matt Gunn","email":"","orcid":"","institution":"Aberystwyth University","correspondingAuthor":false,"prefix":"","firstName":"Matt","middleName":"","lastName":"Gunn","suffix":""},{"id":172672094,"identity":"e8fdbaf2-e31b-486e-b138-23075235532d","order_by":2,"name":"Stephen Fearn","email":"","orcid":"","institution":"Aberystwyth University","correspondingAuthor":false,"prefix":"","firstName":"Stephen","middleName":"","lastName":"Fearn","suffix":""},{"id":172672095,"identity":"1fd5f7e7-f543-4c4e-843a-ec65d38fd2b5","order_by":3,"name":"Tomos Fearn","email":"","orcid":"","institution":"Aberystwyth University","correspondingAuthor":false,"prefix":"","firstName":"Tomos","middleName":"","lastName":"Fearn","suffix":""},{"id":172672096,"identity":"733f38fa-81d3-421a-876b-3d7ca96f3477","order_by":4,"name":"Huw Morgan","email":"","orcid":"","institution":"Aberystwyth University","correspondingAuthor":false,"prefix":"","firstName":"Huw","middleName":"","lastName":"Morgan","suffix":""}],"badges":[],"createdAt":"2023-02-01 11:14:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-2538179/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-2538179/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11207-023-02162-1","type":"published","date":"2023-06-12T21:13:22+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":44731071,"identity":"198fbd93-5b23-46b1-a8aa-44077449ee14","added_by":"auto","created_at":"2023-10-16 21:39:25","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3202107,"visible":true,"origin":"","legend":"","description":"","filename":"2019eclipseSolarPhysicssubmitted.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2538179/v1_covered_1db57eaf-aadc-4ba9-a73d-ee0c05ba8eb3.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eVisible emission line spectroscopy of the solar corona during the 2019 total solar eclipse\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"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},"keywords":" eclipse, visible light spectroscopy, dynamics, magnetic fields, corona","lastPublishedDoi":"10.21203/rs.3.rs-2538179/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-2538179/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Spectroscopic measurements of the low solar corona are crucial to understanding the mechanisms that heat the corona and accelerate the solar wind, yet the lowest solar radii (R⊙) of the corona is difficult to observe. 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